Soria, R;
Graham, AW;
Fabbiano, G;
Baldi, A;
Elvis, M;
Jerjen, H;
Pellegrini, S;
(2006)
Accretion and Nuclear Activity of Quiescent Supermassive Black Holes. II. Optical Study and Interpretation.
The Astrophysical Journal
, 640
pp. 143-155.
10.1086/499935.