000
00258nam a2200109 4500
008
160616s 000 0
245
_a
Free rings and their relations
100
_a
Cohn, P.M
500
_a
B278 L1
942
_c
BK
_2
BK4960
_0
1
080
_a
515.122 COHN
999
_c
4960
_d
4960