$a Water resources and land-use planning : a systems approach : proceedings of the NATO Advanced Study Institute on: "Water Resources and Land-Use Planning", Louvain-la-Neuve, Belgium, July 3-14, 1978 / ed. by P. Laconte and Y. Y. Haimes. - The Hague, 1982. $b (The Expansion Department, University of Louvain, Belgium)