[Clements01] Clements, Paul, and Northrop, Linda, Software Product Lines: Practices and Patterns, Addison Wesley: Boston , 2001.
[Fairley and Willshire03] Fairley, Richard E., and Willshire, Mary Jane, Why the Vasa Sank: 10 Problems and Some Antidotes for Software Projects, IEEE Software (April “May 2003): pp. 18 “25.
[Mullet99] Mullet, Dianna, The Software Crisis, Benchmarks Online ”a Monthly Publication of Academic Computing Services ”a Division of the University of North Texas Computing Center 2(7), July 1999, www.unt.edu/benchmarks/archives/1999/july99/crisis.htm.
RMTrk: www.rmtrak.com/
Rational RequisitePro : www.rational.com/products/reqpro/index.jsp?SMSESSION=NO
Goda Software: www.analysttool.com/
SpeeDEV: www.speedev.com/speedProcess.html
Telelogic: www.software-systems-development.com/
Intrinsyx Technologies: www.intrinsyx.com/technologies/services/requirements.htm