An Empirical Comparison of Some Business Process Notations. - Ahmad Jaffar; Hefin Rowlands; A. Alderson; Martyn Fletcher (IKE, 2003)

Preferences of Business Process Models: Interpretative Analysis on Spontaneously Common Symbols. - Saleh Alwahaishi; Ahmad Jaffar; Ivo Vondrák; Václav Snásel; Jaroslav Pokorný (ISD, 2010)