S. Didar-Al-Alam, S. Shahnewaz, D. Pfahl, и G. Ruhe. Product-Focused Software Process Improvement, том 8892 из Lecture Notes in Computer Science, Springer International Publishing, (2014)
P. Abrahamsson, и J. Koskela. Empirical Software Engineering, 2004. ISESE '04. Proceedings. 2004 International Symposium on, стр. 73--82. (августа 2004)