Translated from the Russian by Yuri Atanov
First published 1981
Second printing 1983
Third printing 1988
Revised from the 1979 Russian edition
Ha ane4141.1C1COM sisbme
Printed in the Union of Soviet Socialist Republics
© English translation, Mir Publishers, 1981
ISBN 5-03-000800-4 © 1/13gaTenbenio «Hapca», FaasHasi pegaxquA
cnisHico-maTemanrgeotoil awrepaTyphi, 1979