Polan, E. U. (2007). Journey across the life span: Human development and health promotion (3rd ed.). F. A. Davis.
Chicago-viite (17. p.)Polan, Elaine U. Journey Across the Life Span: Human Development and Health Promotion. 3rd ed. Philadelphia: F. A. Davis, 2007.
MLA-viite (9. p.)Polan, Elaine U. Journey Across the Life Span: Human Development and Health Promotion. 3rd ed. F. A. Davis, 2007.
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