A Deep Chandra, Very Large Array, and Spitzer Infrared Array Camera Study of the Very Low Luminosity Nucleus of the Elliptical NGC 821 - Pellegrini, S.; Siemiginowska, A.; Fabbiano, G.; Elvis, M.; Greenhill, L.; Soria, Roberto; Baldi, A.; Kim, D. (Institute of Physics Publishing, Inc., 2007)