Παραπομπή APA

Chang, G., & Sederberg, T. W. (1997). Over and over again. Mathematical Association of America.

Παραπομπή Chicago Style

Chang, Gengzhe, και Thomas W. Sederberg. Over and over Again. [Washington, DC]: Mathematical Association of America, 1997.

Παραπομπή MLA

Chang, Gengzhe, και Thomas W. Sederberg. Over and over Again. Mathematical Association of America, 1997.