Cavanaugh, John C.
Cengage Learning, cop, 2015
Buku Teks
Lazarus, Richard S.
Oxford University Press, 2006
Buku Teks
editor, James E. Birren and K. Warner Schaie
Academic Press, 1990
Buku Referensi
K. Warner Schaie, Sherry L. Willis, editor ; Bob G. Knight, Becca Levy, Denise C. Park, associate editors
Elsevier, 2011
Buku Teks
Schultz, Richard
Prentice-Hall, 1999
Buku Teks