Walt Disney Co. said it will begin publishing hardback and paperback books for adult readers in 1991, with 50 titles planned the first year.

The company said it had yet to select a name for the division, although the books won't come out under the Disney name. Robert Miller, 34, is leaving his job as a Dell Publishing vice president to head the operation.Disney, which has expanded its consumer products division aggressively in recent years, created a children's publishing operation in July.