Lotov A.V., (1973), An Approach to Perspective Planning in the Case of Absence of Unique Objective. In: Proc. of Conf. on Systems Approach and Perspective Planning (Moscow, May 1972), Computing Center of the USSR Academy of Sciences, Moscow (in Russian).
and in English in
Lotov A.V. (1989), Generalized Reachable Sets Method in Multiple Criteria Problems, in Methodology and Software for Interactive Decision Support, Lecture Notes in Economics and Mathematical Systems, 337, Springer-Verlag, Berlin.