Pinto-Albuquerque, M. & Rashid, A. (2011). Managing imperfection in requirements: a method and a jigsaw puzzle metaphor. In Brian Berenbach,  Maya Daneva, Jörg Dörr,  Samuel Fricker, Vincenzo Gervasi,  Martin Glinz,  Andrea Herrmann,  Benedikt Krams,  Nazim H. Madhavji,  Barbara Paech,  Sixten Schockert,  Norbert Seyff (Ed.), 17th International Working Conference on Requirements Engineering: Foundation for Software Quality (REFSQ 2011). (pp. 226-233). Essen: Institute for Computer Science and Business Information Systems (ICB), University Duisburg Essen.