Pen, J. (1971). Income distribution. Penguin Books.
Lua i Stíl Chicago (17ú heag.)Pen, J. Income Distribution. Baltimore, Maryland: Penguin Books, 1971.
Lua MLA (8ú heag.)Pen, J. Income Distribution. Penguin Books, 1971.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.