Observations of novae and theoretical results, in which the authors studied the nova outburst by radially accreting H-rich matter onto an He white dwarf, have convinced them that realistic nova models must be based on accretion that includes the angular momentum of the accreting matter. In the present paper the authors develop the theory of accretion onto stars of matter possessing angular momentum, including the shear forces between the accreting matter and the star (assumed to be nonrotating), distribution of accreted matter and its angular momentum by turbulent mixing, thermalizing of rotational kinetic energy, and loss of energy by horizontal expansion. 25 references.