Radio-loud active galaxies in the northern ROSAT All-Sky Survey. II. Multi-frequency properties of unidentified sources.
Journal article published in 1997 by
W. Brinkmann,
J. Siebert,
E. D. Feigelson,
R. I. Kollgaard,
S. A. Laurent-Muehleisen,
W. Reich,
E. Fuerst,
P. Reich,
W. Voges,
J. Truemper,
R. McMahon 
