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Analysis of Open Source Simulation Applications
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Archives of Business Research – Vol.7, No.12
Publication Date: Dec. 25, 2019
DOI: 10.14738/abr.712.7603.
Janamanchi, B. (2019). Analysis of Open Source Simulation Applications. Archives of Business Research, 7(12), 292-306.
Analysis of Open Source Simulation Applications
Balaji Janamanchi
Associate Professor of Management
Division of International Business and Technology Studies
A.R. Sanchez Jr. School of Business, Texas A & M International University
ABSTRACT
This study seeks to understanding the growth and popularity of Open Source Software
(OSS) development for simulation modeling under Science and Engineering domain on
SourceForge online service platform. The objectives include understanding the
importance, if any, of the features such as, license type, programming language,
Operating System version, review rating in influencing the popularity of a given
software application as measured by downloads. For obvious reasons, end-users select
and adopt specific applications based on their usage needs and the suitability of a given
application in meeting their needs. Nevertheless, some applications may be easily
adoptable than the other given the different options available for customization as well
as scalability opportunities present in an application. So, other factors remaining
common, popularity gained by an application with the increased downloads tends to
draw prospective users to a specific application more than the others. This study
analyses the availability and accessibility of simulation modeling software on the
Source Forge website, undeniably, a very large repository of open source software
resources. Limiting the search to “Simulations” within “Science and Engineering”
domain /category. The top 250 applications’ data is downloaded and analyzed. Useful
insights and metrics are developed and compiled to assist end-users to understand the
profile of open source simulation applications available for users for free downloads.
Keywords: Open Source Software, Science and Engineering, Simulation Modeling, Open
Source Licensing.
INTRODUCTION
What is Open Source?
The term "open source" refers to something people can modify and share because its design is
publicly accessible [1]. Essentially, the term open source denotes the accessibility of ‘source
code” underlying any application software that is made available to the end-users so that they
modify the application software to suit their usage needs under rather unrestrictive set of
terms of usage license [1].
As may be logically inferred, users are able to modify, extend, alter, amend and improve the
open source software, as they need or desire, to suit their specific usage requirements.
Contrast this with the most common proprietary software that comes already installed or
users purchase and install on their computers for their use; proprietary software providers do
not allow access to the source course of the software to the end-users. A very limited to no
option is given to end-users to customize functionality and/or fine-tune the features of
proprietary software applications. This, obviously, leads to a dependence on proprietary
software sellers for almost all issues with the use and implementation of applications, whereas
the users of open source software applications are free from such dependence on developers.
Another interesting fact about open source software is that, most open source software is
available “free of cost” to interested end-users as long as they are willing to abide by the usage
license. This means, all end-users big and small can acquire it at practically free of cost and

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possibly, benefit from using the software application for their business needs. Typically, small
and medium enterprise that are more often are cash strapped than not will be able to afford
the open source software as long as they are willing to invest enough time and effort in getting
to know how best to use it to meet their decision support requirements.
What is Source Forge?
“SourceForge is a web-based service that offers software developers a
centralized online location to control and manage free and open-source
software projects. It provides a source code repository, bug tracking, mirroring
of downloads for load balancing, a wiki for documentation, developer and user
mailing lists, user-support forums, user-written reviews and ratings, a news
bulletin, micro-blog for publishing project updates, and other features.” [2].
“SourceForge offers free access to hosting and tools for developers of free /
open-source software. As of March 2014, the SourceForge repository claimed to
host more than 430,000 projects and had more than 3.7 million registered
users. The domain sourceforge.net attracted at least 33 million visitors by
August 2009 according to a Compete.com survey.” [2]
From the above it may be noted that SourceForge is a common shared forum where
independent software developers can upload and host software applications they created for
others to see and appreciate and possibly download and use, improve share further with
others. This may be likened to artifact emerging from a loosely put together collaborative
project effort by team members that may not ever meet or know each other, of the team.
Currently, SourceForge is not the top ranked forum for open source software [3]. Nevertheless,
SourceForge is the first such forums to provide a centralized location to host opensource
software for developers and users free of cost some twenty years in November of 1999. As per
table 1 below, based on Alexa rankings SourceForge ranks #2 among the source code hosting
facilities, second to GitHub [3].
Table 1: Source Code Hosting facility by Popularity [3]

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What is Simulation?
“Simulation refers to a broad collection of methods and applications to mimic the behavior of
real systems, usually on a computer with appropriate software” [4]. In fact, simulation is used
and applied in many fields and contexts to get a better understanding of complex behavior of
systems in order to manage them better. Typically, simulation is useful in situations or context
where an analytical solution does not exist due to complexity of the behavior system variables
or other attendant features. The author has used and been using a type of simulation modeling
in researching Supply Chain Management [5] and Project Management [6] related issues.
Simulation modeling is creation of computer models of some activity, process or phenomena
for the purpose of study by manipulating it logically to understand how the real physical world
works. Simulation helps to answer questions that are otherwise to be learned by
experimenting with real systems and in many situations, conducting experiments on real
system is impossible, impractical, or prohibitively expensive. For example: consider using flight
simulators instead of flying real aircraft at the beginning stages of a pilot’s training.
Who, when, where, and why of Simulation.
Any standard simulation book provides in its introduction section or the first chapter answers
to the basic questions of who uses simulation. When is simulation useful? Alternatively, what
context is simulation most useful? Why to use simulation? What are the limitations of
simulation? Suffice it to recount here that simulation is used in a wide variety of fields and
industries. It is most useful where analytical solutions do not exist. A curious reader wanting
know more details about simulations and its use, is well advised to refer to a fairly effective
contribution to the Winder Simulation Conference 2004 by Carson [7]. As is well known, all
managers, decision makers need as much decision support as they can get when dealing with
complex business situations. Whoever needs to make effective decisions need decision support
tools in making better decisions will most likely at some point in time to simulation for help
and guidance.
CURRENT STUDY- PURPOSE AND OBJECTIVE
As stated earlier most business enterprises as well as individual users can benefit from using
simulation models, tools for decision support in their daily routines. However, lack of suitable
and affordable tools/options and the financial costs in many cases become a big hurdle. Not
much attention is given in academic literature to the availability of and characteristics of open
source Simulation Software (OSSS). Further, this study also seeks to understand the user
activity on the SourceForge in respect of the simulation modeling to learn about success of OSS
simulation modeling applications. This study explores these issues with an analysis of
Simulation Software under Open source projects on Source-Forge, a large repository of open
source projects. The idea is to assess the available cost-free resources for simulation that may
be accessible and useful to small and medium business organizations that may not be able to
afford expensive proprietary software alternatives.
DATA COLLECTION PROCESS
Data Search on Sourceforege
The data was gathered using the open source software website www.sourceforge.net.
Collection of the data started on September 28 and finished on October 2, 2016. By using the
browse option on the website, it was possible to limit the search to “Science and Engineering”
domain and by looking up the available options by typing in the key words “Simulation
Software” in the search field. A whopping 101 pages of results showed up with 25 items per
page totaling a little over 2,500 different item of software. We then limited our analysis to the
top 250 results from these. There are different options to sort the results and we used the most

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intuitive option of sorting by popularity. The analysis and discussions presented herein under
the sections to follow is based on this shortlist of 250 software applications.
Metrics recorded and date of collected
For each of these 250 Simulation software in the Science and Engineering field, the following
data was collected: Software Name, Registered Date, Last Updated Date, Intended Audience,
Programming Language, Languages Available, OS Versions Available, Review & Rating,
Downloads, Top Downloaded Country, Top Downloaded OS, and License Type (subsequently)
totaling 12 variables each. Any missing data was highlighted in the spreadsheet, but was not
imputed. Instead, the analyses are performed based on the available data under the respective
fields.
ANALYSIS AND FINDINGS
As stated under the data collection section, for each of the 250 Simulation Software
Applications found under “Science and Engineering” classification, details of twelve attributes
were collected. The idea in gathering these items of data about each of the application is to
provide the potential end-users a reasonably good understanding of the profile of successful
OS Simulation applications so that they may choose the right application for their purposes.
Figure 1: Histogram of Intended Audience
In developing the above chart, only those categories that had > 1% out of 250 observations
were captured distinctly. All other designations of intended audience with 2 or 1 (being <1% in
250) were combined under the broad category of “other” which turned out to be largest group

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with 135 out of 250 observations. This is very interesting in that, these applications appear to
target very specific and distinct intended audience from each other.
Amongst the distinctly captured groups of intended audience, “scientific research” is the single
largest. Further, scientific research in combination with other categories of audience accounts
for 62 observations, which is to be expected since the observations were selected from the
“Science and Engineering” domain.
The other noteworthy point in the above histogram is the group of “Developers” and
combinations containing developers. On careful review, one might conclude that this is not
surprising given that most developers would expect other developers to extend their
applications by taking from where they left off and build the application to the next level of
user-friendliness.
Figure 2: Histogram of projects by the OS version available
As shown in Figure 2, Windows and Windows combined with other OS appear to dominate the
field, followed by Linux and Mac. It’s interesting to note that while applications are open
source, the preferred OS for developing the applications is proprietary Windows (by Microsoft
Corpn) rather than Linux or other open source Operating systems.
Generally speaking Open Source software license categories form a spectrum ranging from
highly restrictive e.g. GNU AGPLv3 through moderately restrictive e.g. GNU LGPLv3,
moderately permissive e.g. Apache License 2.0, highly permissive e.g. MIT License, and ending
with Unlicense e.g. public domain [8]. Not surprisingly, restrictive licenses tend to attract

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developers more than end-users because restrictive licenses place restrictions and obligations
on the user of the respective application that only seasoned developers can navigate. On the
other hand, highly permissive and unlicense types will be of great interest to end-users more
than developers for obvious reasons.
Detailed explanation for various license is available at the Open Source Initiative website [9].
Figure 3 below shows the distribution of license types among the Open Source Simulation
applications. As may be seen from it, GNU GPLv2 is the most popular license type. There is a
widespread of license types other than GNU GPL v2 and its variations.
Figure 3: Count of project by their license type
As far as the preferred programming language is concerned, Figure 4 below shows Java to be
the single most popular with 65 out of 250 accounting for slightly more than 25% of the top
250 applications. However, C++ and its combinations combined add up to 71 out of 250.
Python appears to emerge as significant third with 26 application of the 250 using it as their
preferred language for application development. Given that the domain is Science and
Engineering, MATLAB also found fair following in OS Simulation application development.

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Figure 4: Programming Language
Review and rating of an application by the users is a reasonably good measure of the
usefulness and ease-of-use features of the application. Figure 5 depicts the review ratings of
the top 250 applications under the study. As may be noted, 60% of the applications received a
rating of three or higher out of a possible five score. Nearly 42% of the 250 applications
received 5 out of 5 perfect score from their users. This is a very encouraging sign in that not
only the software applications are available under open source initiative (presumably, free-of-
cost) but are of top quality applications as rated by the discerning end-users.
However, one point of concern could be that as many as 94 applications have not been
reviewed or rated among the top 250. It is not clear if they were not rated because the users
didn’t like them but didn’t want to leave negative comments/ or poor ratings. Alternatively,
that the software application is in trial version and not yet open for reviews and rating. In
either case, this could potentially be a concern given that these 94 applications already found
their place in the top 250-simulation software on the forum without yet receiving ratings from
the end-users.

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Figure 5: Count of projects by their review ratings
Although downloads metric doesn’t always guarantee the usage of downloaded software, in the
context of an OSS community downloads could be an effective metric for the popularity of an
application in that downloads evidences interest in the applications by the target audience. So
downloads metric is arguably a good proxy to popularity of an application or that of a
programming language used or license type etc. We analyzed the data in respect of downloads
in multiple perspectives and results are depicted as cross tabulations and discussed below.

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Figure 6: Count of projects by the top downloaded country
We begin with the presentation of top downloaded application count by country in Figure 6
above. As may be seen from Figure 6, the Open source software usage and awareness appears
to be widespread in the US more than any other country in the world. As a matter of fact the
total number of applications downloaded the most (top downloaded) in US at 175 out of 250 is
more than twice as many as all other countries combined, which is only 75 out of 250.
Noteworthy from the figure 6 is the fact that China and India are #2 and #3 in downloading 16
and 14 distinct simulation applications the most number of times compared to any other
country in the world having access to these Open source simulation software applications.
Given that this chart is for the count of “most downloaded country” one cannot read too much
into it without overlooking other important aspects of open source software usage.

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Figure 7: Cross tabulation of Mean Downloads by License type
Figure 7 captures the mean weekly downloads by the license type. By far the downloads of
software provided under restrictive license types such as GNU GPL v2 and its variations appear
to dominate the scenario. However, aside of that there is a reasonable distribution among
moderately and highly permissive license types. This is a little counterintuitive in that it is
commonly believed that only programmers and advanced end-users prefer the restrictive
license than a novice end-user or a person not very adept at modifying source code files. So one
would expect more downloads of unrestrictive and highly permissive license categories of
application than the restrictive ones. Therefore, this phenomenon needing further exploration
to understand the underlying dynamics.

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Figure 8: Cross tabulation of Mean Downloads by the Programming Language
Figure 8 above clearly establishes that Java is the single most popular software for developing
these Open Source Simulation software by leading the average weekly. The other bar that is
bigger than java is, actually, a group of four different software. These four seem to combine
well in that the developers decide to release their application in all four at the same time.
Further programming language C and C++, C# and combinations seem to account for sizeable
downloads as well.
While the use of programming language by the count of projects may indicate the developers’
preference for a language, the weekly downloads tabulated by the programming languages
may indicate the end-user preference for a specific software. It may also indicate the feature
richness of the specific software as well as the support for on online forums and other aspects.
Over a period, the developers may be influenced by the end user’s choice of software and
decide to switch to those rather than to stick to their personal preferences. Or a new section of
developers may emerge that will convert existing Open source applications from less popular
software languages into applications developed in more popular software. Given that some big
name corporations from IT industry are actively sponsoring new projects in Open Source
platforms, we may see more and more of the latter of above said two outcomes.
In figure 9 depicts the top 10 project by the weekly downloads in October 2017. As may the
seen, the top most software’s downloads are way more than the weekly downloads of the rest
of the nine software downloads combined.
In order to provide the readers a more recent state of the Open source software in simulation,
figure 10 depicts the top 10 projects by the weekly downloads in December 2019. While the
popularity of the top of the list appears to wane a little bit (down from 131,283 to 87,670) it
nevertheless continues to dominate this segment of open source domain. Seven of the top 10
from October 2017 continue to be in top 10 of December 2019, some with slight change of
ranks while there are three new names at # 3, #7, and #10 in the top 10 of December 2019.

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Figure 9: Weekly downloads of active software applications October 2017
Figure 10: Weekly downloads of active software applications December 2019
The Top Ten Applications
Sweet Home 3D (GPLv2): Sweet Home 3D is an interior design application that helps you to
quickly draw the floor plan of your house, arrange furniture on it, and visit the results in 3D.
With the help of Sweet Home 3D users can draw walls and rooms upon the image of an existing
plan, on one or more levels, drag and drop doors, windows and furniture from a catalog onto
the plan. This application is available in over 25 languages viz. Korean, French, Ukrainian,
Dutch, Polish, Slovene, Czech, Finnish, Italian, Greek, Vietnamese, English, Portuguese, Serbian,
Chinese (Traditional), Bulgarian, Swedish, Turkish, Brazilian Portuguese, Chinese (Simplified),

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German, Japanese, Spanish, Russian, and Hungarian. This might explain the immense
popularity of this application in contrast to other items in this top 10 list because most others
are available in fewer languages with some software limited to just a language or two at most.
The above details and more about this application are given on its webpage in SourceForge
pages [10].
gretl (GPLv3): gretl is a cross-platform software package for econometric analysis, written in
the C programming language. It is claimed to be easy and intuitive GUI based. Offers
sophisticated features of OLS, MLE, GMM and system estimation. Further it is internationalized
with offering in 10 languages besides English. The above details and more about gretl are given
on its webpage in SourceForge pages [11].
Logisim (GPLv2): Logisim, is an educational tool for designing and simulating digital logic
circuits. Featuring simple-to-learn interface, hierarchical circuits, wire bundles, and a large
component library, as a Java application, it can run on many platforms. However, with the last
update recorded as 4/29/2013, the project appears to be abandoned by the developers and
could be categorized as ‘abandonware!’ Surprisingly, Logisim find a place in the December
2019 list of top 10 as well. The above details and more about Logisim are given on its webpage
in SourceForge pages [12].
GNS3 (GNU GPLv2): GNS3 is a graphical network simulator that allows you to design complex
network topologies. You may run simulations or configure devices ranging from simple
workstations to powerful Cisco routers. It is based on Dynamips, Pemu/Qemu and Dynagen.
It’s available in 18 different world laguages that contributes its popularity. The above details
and more about Logisim are given on its webpage in SourceForge pages [13].
mp3splt (GNU GPLv2): mp3splt is a free utility to split mp3, ogg vorbis and FLAC files without
decoding, selecting begin/end time. It also splits Mp3Wrap and AlbumWrap archives. Supports
splitting and trimming by silence detection. It’s available in five different world languages. The
above details and more about mp3splt are given on its webpage in SourceForge pages [14].
OS X Portable Applications (GPLv2): OS X FOSS portable applications are packaged so one
can carry around on any portable device, USB thumb drive, iPod, portable hard drive, memory
card, other portable device (or also on one’s internal hard disk), taking their preferences with
them. All these details and more about OSX Portable Applications are given on its webpage in
SourceForge pages [15].
OpenRocket (GPLv3): An Open Source model rocket simulator. Claims to provide, everything
you need to design, simulate and fly better rockets. More of hobby project but available in five
different world languages contributing to its success all over the world. All these details and
more about OSX Portable Applications are given on its webpage in SourceForge pages [16].
SAGA GIS (GPLv2):
SAGA - System for Automated Geoscientific Analyses - is a Geographic Information System (GIS)
software with immense capabilities for geodata processing and analysis. SAGA is programmed in
the object oriented C++ language and supports the implementation of new functions with a very
effective Application Programming Interface (API). Functions are organised as modules in
framework independent Module Libraries and can be accessed via SAGA’s Graphical User
Interface (GUI) or various scripting environments (shell scripts, Python, R ...). [17].

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Java Neural Network Framework Neuroph (Apache License v2.0): Neuroph is lightweight
Java Neural Network Framework which can be used to develop common neural network
architectures. Small number of basic classes which correspond to basic NN concepts, and GUI
editor makes it easy to learn and use. All these details and more about OSX Portable
Applications are given on its webpage in SourceForge pages [18].
CoolProp (MIT License): A cross-platform, open-source, alternative to NIST REFPROP. Based
on reference-accuracy equations of state and transport property correlations for refrigerants
like Water, CO2, R134a, Nitrogen, Argon, Ammonia, Air, R404a, R410a, Propane and many
others. All these details and more about OSX Portable Applications are given on its webpage in
SourceForge pages [19].
LIMITATIONS AND CONCLUSIONS
Limitations
As stated in the introduction, this study is limited to Open Source Simulation Software from SorceForge
repository alone. While Sourceforge is the oldest such repositories, it is currently second in Alexa
ratings with GitHub occupying the first place. Further, this study is limited to simulation software in the
Science and Engineering domain. It is quite likely the simulation software in other domains may rather
different characteristics.
Conclusions:
Based on the charts created, descriptive statistics computed and the analyses performed from
the data collected, the following important observations may be made.
• Eight of the top ten most downloaded Open Source Simulation software on Sourceforge
downloaded in USA (3 to 10). Top project is most downloaded in Russia and second
ranked project is most downloaded in Germany.
• Nine of the top ten are most downloaded on Windows OS versions except for one
ranked 6th which is most downloaded in its MAC OS version.
• First Eight of top ten offer GNU (GPLv2 or GPl3) while the ninth offers Apache License V
2.0 and tenth MIT license
• Not surprisingly, most applications appear to target “End-users, Advanced end users,
scientific research”
• Java, Java script, C and C++ appear to be most preferred programming language
• A very active OSS community in developing Simulation Modeling software with updates
as recent as the week of data collection.
• Despite losing its place of pride as the top forum for OSS projects to GitHub,
SourceForge continues to attract large number of developers and users
• Perhaps, users are accustomed to the SourceForge interface or they come for the old
projects that are continued to be hosted here
Depending upon their respective objectives, readers may find these observations and
conclusions useful for their future use of open source simulation software. The readers may
also find these observations useful for planning their own participation as developers,
sponsors, end-users or other stakeholders on SourceForge and other similar open source
repositories.
References
[1]. Opensource 2019 at URL: https://opensource.org/faq#osd accessed on 12/1/2019
[2]. Wikipedia page on Sourceforge at URL: https://en.wikipedia.org/wiki/SourceForge accessed on 12/1/2019
[3]. Wikipedia page on source code hosting facilities at URL:
https://en.wikipedia.org/wiki/Comparison_of_source-code-hosting_facilities accessed on 12/1/2019

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URL: http://dx.doi.org/10.14738/abr.712.7603.
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[4]. Kelton W.D., Sadowski, R.P., and Sturrock, D.T., Simulation with Arena, 4th edition, 2007 McGraw Hill, New
York, USA. pp1.
[5]. Janamanchi, B and Burns, J., “Control Theory Concepts Applied to Retail Supply Chain: A System Dynamics
Modeling Environment Study” - Journal of Modeling and Simulation in Engineering- Volume 2013, Article ID
421350, 14 pages.
[6]. Burns, J., and Janamanchi, B. “The Dynamics of Change Management in a Technology Project Context,” The
International Journal of Information Systems and Change Management 2006, Volume 1, No.2, pp 115-137
[7]. Carson, J.S. “Introduction to Modeling and Simulation,” Proceedings of the 2004 Winter Simulation
Conference, at URL: https://dl.acm.org/citation.cfm?id=1161740 accessed on 12/1/2019.
[8]. Choosealicense.com at URL https://choosealicense.com/licenses/ accessed on 12/1/2019.
[9]. Opensource 2019 at URL: https://opensource.org/licenses/category accessed on 12/1/2019
[10]. Sweet Home 3D details on Sourceforge at URL: https://sourceforge.net/projects/sweethome3d/ accessed
on 10/2/2017
[11]. gretl on Sourceforge at URL: https://sourceforge.net/projects/gretl/?source=directory accessed accessed on
10/2/2017
[12]. Logisim on Sourceforge at URL: https://sourceforge.net/projects/circuit/?source=directory accessed on
10/2/2017
[13]. GNS3 on Sourceforge at URL: https://sourceforge.net/projects/gns-3/?source=directory accessed on
10/2/2017
[14]. mp3splt on Sourceforge at URL: https://sourceforge.net/projects/mp3splt/?source=directory accessed on
10/2/2017
[15]. OSX Portable applications on Sourceforge at URL:
https://sourceforge.net/projects/osxportableapps/?source=directory accessed on 10/2/2017
[16]. OpenRocket on Sourceforge at URL: https://sourceforge.net/projects/openrocket/?source=directory
accessed on 10/2/2017
[17]. SAGA GIS on Sourceforge at URL: https://sourceforge.net/projects/saga-gis/?source=directory accessed on
10/2/2017
[18]. Java Neural Network Framework Neuroph on Sourceforge at URL:
https://sourceforge.net/projects/neuroph/?source=directory accessed on 10/2/2017.
[19]. CoolProp on Sourceforge at URL:
https://sourceforge.net/projects/phpcollab/?source=directory accessed on 10/2/2017.