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Spectrscopic monitoring of active galactic nuclei. 3 : Size of the broad line region in NGC 3227I. Salamanca, I. Wanders, D. Alloin et al.|Leiden Repository (Leiden University)|1994Cited by 4
Monitoring of active galactic nuclei. I - The quasars 1302 - 102 and 1217 + 023N. Jackson, S. J. Wagner, P. T. O’Brien et al.|Leiden Repository (Leiden University)|1992Cited by 2
Spectroscopic monitoring of active galactic nuclei. II: The Seyfert-1 galaxy NGC 3516I. Wanders, R. Williams, E. van Groningen et al.|Unknown|1993Cited by 1