ebrary, Inc, & Francis, R. G. (1958). The population ahead. University of Minnesota Press.
Chicago Style (17th ed.) Zitazioaebrary, Inc, eta Roy G. Francis. The Population Ahead. Minneapolis: University of Minnesota Press, 1958.
MLA (9th ed.) Zitazioaebrary, Inc, eta Roy G. Francis. The Population Ahead. University of Minnesota Press, 1958.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.