Havighurst, R. J. (1972). Development tasks and education (3rd ed.). David McKay Company, Inc..
Chicago-viite (17. p.)Havighurst, Robert James. Development Tasks and Education. 3rd ed. New york: David McKay Company, Inc., 1972.
MLA-viite (8. p.)Havighurst, Robert James. Development Tasks and Education. 3rd ed. David McKay Company, Inc., 1972.
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