ed. by Robert Hanham, William G. Vogt, Marlin H. Mickle.Modeling and Simulation Conference (16th : 1985 : Pittsburgh):Modeling and simulation.16, pt.1,Geography-regional science.Instrument Society of America,1985.
ed. by E. Casetti, etc..Modeling and Simulation Conference (15th : 1984 : Pittsburgh):Modeling and simulation.15, pt.1,Geography-regional science.The Univ. Pr.,,1984.