Application and Theory of Petri Nets: 20th International Conference, ICATPN'99, Williamsburg, Virginia, USA, June 21-25, 1999 Proceeding: 1999: 20th International Conference, Williamsburg, Virginia, USA, June 21-25, 1999 - Proceedings: 20th International Conference, Williamsburg, Virginia, USA, June 21-25, 1999 - Proceedings by Springer-Verlag Berlin and Heidelberg GmbH & Co. KG (Paperback, 1999)