Παραπομπή APA

Howie, J. M. (1976). Introduction to semigroup theory. Academic Press.

Παραπομπή Chicago Style

Howie, John M. Introduction to Semigroup Theory. London ; New York: Academic Press, 1976.

Παραπομπή MLA

Howie, John M. Introduction to Semigroup Theory. Academic Press, 1976.