000
003020000a22001330004500
245
_a
Operational mathematics
100
_a
Churchill, Ruel V.
250
_a
2nd ed.
260
_a
New York
_b
McGraw Hill
_c
1958
300
_a
ix, 337p. : ill.
080
_a
517.56
_b
C5
041
_a
EN
942
_c
BK
999
_c
51547
_d
51547