SCHULLER ROBERT H. (1991). BE HAPPY ATTITUDES: 8 POSITIVE ATTITUDES THAT CAN TRANSFORM YOUR LIFE. BANTAM BOOKS.
Lua i Stíl Chicago (17ú heag.)SCHULLER ROBERT H. BE HAPPY ATTITUDES: 8 POSITIVE ATTITUDES THAT CAN TRANSFORM YOUR LIFE. NEW YORK: BANTAM BOOKS, 1991.
Lua MLA (9ú heag.)SCHULLER ROBERT H. BE HAPPY ATTITUDES: 8 POSITIVE ATTITUDES THAT CAN TRANSFORM YOUR LIFE. BANTAM BOOKS, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.