view Abstract Citations (173) References (16) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Compact Extragalactic Nonthermal Sources Strittmatter, P. A. ; Serkowski, K. ; Carswell, R. ; Stein, W. A. ; Merrill, K. M. ; Burbidge, E. M. Abstract Results of photometry, polarimetry, spectroscopy, and direct photography at visual wavelengths of four additional objects of the BL Lacertae type are reported together with infrared observations to = 10 of one of them (OJ 287). The data indicate that these objects are compact sources of nonthermal continuum radiation. They are llkely to be extragalactic, and their possible relationship to QSOs is discussed. Publication: The Astrophysical Journal Pub Date: July 1972 DOI: 10.1086/180974 Bibcode: 1972ApJ...175L...7S full text sources ADS | data products NED (7) SIMBAD (5)