(1991). Variability of active galaxies: Proceedings of a workshop of the Sonderforschungsbereich 328, held at Heidelberg, Germany, 3-5 September 1990 / W.J. Duschl, S.J. Wagner, M. Camenzind, eds.
Chicago-referens (17:e uppl.)Variability of Active Galaxies: Proceedings of a Workshop of the Sonderforschungsbereich 328, Held at Heidelberg, Germany, 3-5 September 1990 / W.J. Duschl, S.J. Wagner, M. Camenzind, Eds. 1991.
MLA-referens (9:e uppl.)Variability of Active Galaxies: Proceedings of a Workshop of the Sonderforschungsbereich 328, Held at Heidelberg, Germany, 3-5 September 1990 / W.J. Duschl, S.J. Wagner, M. Camenzind, Eds. 1991.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.