Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. II - an intensive study of NGC 5548 at optical wavelengths
Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. IV - Intensity variations of the optical emission lines of NGC 5548
Steps toward determination of the size and structure of the broad-line region in active galatic nuclei. 8: an intensive HST, IUE, and ground-based study of NGC 5548