M. S. Gabrielyan and A. G. Matevosyan, “MINIMAX AIMING AT SEVERAL TARGET SETS FOR STAGE BY STAGE VARYING PROPER LINEAR STOCHASTIC SYSTEMS”, Proc. YSU A: Phys. Math. Sci., vol. 37, no. 2 (201), pp. 25–29, Jun. 2003, doi: 10.46991/PYSUA.2003.37.2.025.