Cita APA (7th ed.)

Leland, H., & Smith, D. E. (1974). Mental retardation: Present and future perspective. C. A. Jones.

Cita Chicago (17th ed.)

Leland, Henry, i Daniel E. Smith. Mental Retardation: Present and Future Perspective. Worthington, Ohio: C. A. Jones, 1974.

Cita MLA (9th ed.)

Leland, Henry, i Daniel E. Smith. Mental Retardation: Present and Future Perspective. C. A. Jones, 1974.