000
00291nam a2200121Ia 4500
008
210901s1972 xx 000 0 eng d
082
_a
512.897 OPE
100
_a
Open University
245
0
_a
Boundary value problems
260
_b
Open University
_c
1972
300
_a
36p.
942
_2
ddc
_c
BK
999
_c
10413
_d
10413