Observations of Cosmic X-Ray Sources Above 20 KeV from OSO-8 (Abstract) Dennis, B. R. ; Crannell, C. J. ; Doian, J. F. ; Frost, K. J. ; Orwig, L. E. ; Beall, J. H. ; Maurer, G. F. Abstract Publication: International Cosmic Ray Conference Pub Date: 1977 Bibcode: 1977ICRC....1..160D