000 00298nam a2200121Ia 4500
100 _aSernadas, A.
020 _a0-444-87706-1
942 _cBK
245 _aInformation systems
_btheoretical and formal aspects
260 _aNorth- Holland, Amsterdam
_c1985
082 _a001.64 Ser
300 _ax,237
999 _c17250
_d17250