00608nam a2200181Ia 4500 IN-BaIIA 211028s9999 xx 000 0 eng d IIA Library 017:52-73 EIN.4 Einstein Catalog Committee 21183 Einstein observatory catalog of IPC x-ray sources vol. 4 Einstein Catalog Committee Cambridge Smithsonian Astrophysical Observatory 1990 iii, 528p. v.4 Catalog-Imaging propotional counter. 21184 X-Ray sources 12440 BK 12145 12145 0 0 ddc 0 0 BAN BAN GEN 1997-07-08 0 017:52-73/ EIN.4 13061 2021-11-05 1997-07-08 BK