Photograph G.I. Marchuk's 50th birthday. A picnic on the beach. A.S. Alekseev (2nd from the left), A.P. Ershov (3rd from the left) Date: 07.06.1975 Original document language: russian Persons: Anatoly S. Alekseev, Andrei Petrovich Ershov, Guri I. Marchuk