APA

Smelser Neil J, Baltes Paul B, . (2001). International encycloopedia of the Social and behavioral sciences Vol. XX. New York: ELSEVER.

Chicago

Smelser Neil J, Baltes Paul B, . 2001. International encycloopedia of the Social and behavioral sciences Vol. XX. New York: ELSEVER.

Harvard

Smelser Neil J, Baltes Paul B, . (2001). International encycloopedia of the Social and behavioral sciences Vol. XX. New York: ELSEVER.

MLA

Smelser Neil J, Baltes Paul B, . International encycloopedia of the Social and behavioral sciences Vol. XX. New York: ELSEVER. 2001.