APA (7 ম সংস্করণ) উদ্ধৃতি

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

শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতি

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

M.L.A (9 ম সংস্করণ) উদ্ধৃতি

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