TY - GEN AU - Makanin, G. S. AU - Leifman, Lev. J. AU - TI - EIGHT LECTURES DELIVERED AT THE INTERNATIONAL CONGRESS OF MATHEMATICIANS IN HELSINKI U1 - 510 PY - 1981/// CY - Providence, R. I. PB - American Mathematical Society KW - Mathematics -- Congresses N1 - Translation In Russian ER -