00317nam a2200121Ia 4500008004100000082001500041100002000056245002600076260004300102300001000145630002800155650001200183211109s9999||||xx |||||||||||||| ||und||  a520bBER-D  aBerg, Rebecca M 0aDescriptive Astronomy  bD.Van Nostrand CompanyaNew Yorkc1978  a317p.  xPost Graduate Reference  vPhysics