Berk, L. E. (1997). Child development (4th.ed.). Allyn and Bacon.
Dyfyniad Arddull ChicagoBerk, Laura E. Child Development. 4th.ed. Boston: Allyn and Bacon, 1997.
Dyfyniad MLABerk, Laura E. Child Development. 4th.ed. Allyn and Bacon, 1997.
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