2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/9955We show that viscous, transonic accretion disks which start with sub-Keplerian angular momentum at the outer boundary reproduce the features of the so-called thick, thin, slim and other accretion disk models depending upon the accretion rates and viscosity parameters. These disks are advection dominated in the pre-shock region and rotation dominated in the post-shock region when viscosity is less than a critical value. For a higher viscosity the shock disappears, and the flow has significant radial velocity only close to the black hole.4 pages, Latex. Two figures available upon request. Proceedings of 17th Texas Symposium (Munich, Dec. 1994)Astrophysicstext