Gaya APA
Duska, R., Whelan, M. (1975).
Moral Development : a guide to piaget and kohlberg .
New York:
Macmilla Publishers Group.
Gaya MLA
Duska, Ronald., Whelan, Mariellen.
"Moral Development : a guide to piaget and kohlberg".
New York:
Macmilla Publishers Group,
1975.
Text.