T. Niinimaki, A. Piri, и C. Lassenius. Global Software Engineering, 2009. ICGSE 2009. Fourth IEEE International Conference on, стр. 153-162. (июля 2009)
E. Piri, M. Hirvonen, и J. Laulajainen. TRIDENTCOM, том 90 из Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, стр. 255-270. Springer, (2011)