William Damon, editor-in-chief
John Wiley & Sons, 1998
Buku Referensi
Maier, Henry W
Harper and Row, 1978
Buku Teks
Kathleen McCartnet; Deborah Phillips
Blackwell, 2006
Buku Teks
William Damon, editor-in-chief
John Wiley & Sons, 1998
Buku Referensi
Santrock, John W., author
McGraw-Hill, 1998
Buku Teks