Twente, E. E. (1970). Never too old: The aged in community life. Jossey Bass.
Chicago-viite (17. p.)Twente, Esther E. Never Too Old: The Aged in Community Life. San francisco: Jossey Bass, 1970.
MLA-viite (9. p.)Twente, Esther E. Never Too Old: The Aged in Community Life. Jossey Bass, 1970.
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