@book{9537,
	author = {Workshop on "Generalized Concavity Fractional Programming and Economic Applications", University of Pisa, Italy, May 30-June 1, 1988 and Comobini, A.},
	title = {Generalized convexity and fractional programming with economic applications; proceedings of the international workshop},
	publisher = {Springer-Verlag,},
	year = {1990},
	address = {Berlin:}
}