Here are a few things you should know about complex systems, result of a worldwide collaborative effort from leading experts, practitioners and students in the field.
A. Gregoriades, J. Shin, and A. Sutcliffe. 12th IEEE International Requirements Engineering Conference, page 154--163. Washington, DC, USA, IEEE Computer Society, (2004)
A. Sutcliffe. RE '01: Proceedings of the Fifth IEEE International Symposium on Requirements Engineering (RE '01), Washington, DC, USA, IEEE Computer Society, (2001)