000			00397nam a2200133Ia 4500
008			211109s9999||||xx |||||||||||||| ||und||
082			_a521.18 _bBAL-T
100			_aBalthaser H,
245		0	_aTwo Say Why
260			_bSheed and Ward _aNew York _c1976
630			_xGENERAL STACK
650			_aNATURAL SCIENCE& MATHEMATICS _vASTRONOMY & ALLIED SCIENCE _xCELESTIAL MECHANICSGeneralia
942			_cBOOK
999			_c68023 _d68023