Okun, M. A. (1982). Programs for older adults. Jossey-Bass Inc..
Lua i Stíl Chicago (17ú heag.)Okun, Morris A. Programs for Older Adults. San Francisco: Jossey-Bass Inc., 1982.
Lua MLA (9ú heag.)Okun, Morris A. Programs for Older Adults. Jossey-Bass Inc., 1982.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.