Schuller, R. (1985). The be happy attitudes: Eight postive attitudes that can transform your life. Word books.
Chicago-referens (17:e uppl.)Schuller, Robert. The Be Happy Attitudes: Eight Postive Attitudes That Can Transform Your Life. Texas: Word books, 1985.
MLA-referens (9:e uppl.)Schuller, Robert. The Be Happy Attitudes: Eight Postive Attitudes That Can Transform Your Life. Word books, 1985.
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