Eutrophication of shallow lakes : modeling and management : the Lake Balton case study : proceeding of a workshop organized by the Hungarian Academy of Sciences, IIASA, the Hungarian National Water Authority, and the Hungarian Committe for Applied Systems Analysis, 29 August-3 Septemer 1982, Veszprém, Hungary / edited by L. Somlyódy, in collaboration with S. Herodek and J. Fischer.