APA aipamena

Spengler, J. J. (1972). Population economics: Selected essays of Joseph John Spengler. Duke University Press.

Chicago Style aipamena

Spengler, Joseph John. Population Economics: Selected Essays of Joseph John Spengler. Durham, North Carolina: Duke University Press, 1972.

MLA aipamena

Spengler, Joseph John. Population Economics: Selected Essays of Joseph John Spengler. Duke University Press, 1972.