000 00312nam a2200133Ia 4500
008 220721s1991 xx 000 0 und d
041 _aeng
082 _a614.7(5482)
100 _aDigram, G.
245 _aEnvironment On File
260 _aU.S.A
_bFacts On File
_c1991
300 _a175P.
999 _c81978
_d81978