Charles Herring Simon M. Kaplan Viable Systems: The Control Paradigm for Software Architecture Revisited. 97-106 2000 conf/aswec/2000 Australian Software Engineering Conference http://csdl.computer.org/comp/proceedings/aswec/2000/0631/00/06310097abs.htm db/conf/aswec/aswec2000.html#HerringK00