APA-viite (7. p.)
WARREN, S. (1987). AN OPTIMAL LEARNING ENVIRONMENT FOR INFANTS AND TODDLERS WITH SEVERE HANDICAPS.
Chicago-viite (17. p.)
WARREN, S.F. AN OPTIMAL LEARNING ENVIRONMENT FOR INFANTS AND TODDLERS WITH SEVERE HANDICAPS. 1987.
MLA-viite (9. p.)
WARREN, S.F. AN OPTIMAL LEARNING ENVIRONMENT FOR INFANTS AND TODDLERS WITH SEVERE HANDICAPS. 1987.
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