J. Linåker, B. Regnell, and H. Munir. Proceedings of the 2015 International Conference on Software and System Process, page 208--212. New York, NY, USA, ACM, (2015)
R. Berntsson Svensson, and B. Regnell. Requirements Engineering: Foundation for Software Quality, volume 9013 of Lecture Notes in Computer Science, Springer International Publishing, (2015)