Cita APA (7th ed.)
WILLIAMS, R. (1989). PERCEPTIONS OF MENTALLY RETARDED PERSONS.
Cita Chicago (17th ed.)
WILLIAMS, R.F. PERCEPTIONS OF MENTALLY RETARDED PERSONS. 1989.
Cita MLA (9th ed.)
WILLIAMS, R.F. PERCEPTIONS OF MENTALLY RETARDED PERSONS. 1989.
Atenció: Aquestes cites poden no estar 100% correctes.