P. Wiemer-Hastings. Proc. of the 16th International Joint Conference on Artificial Intelligence
(IJCAI), page 932--937. Stockholm, Sweden, Morgan Kaufmann, (August 1999)
M. Watson-Manheim, K. Crowsten, and K. Chudoba. Proceedings of the 35th Annual Hawaii International Conference on
System Sciences (revised version), (2002)