Singer, P. (2018). Marx: A Very Short Introduction (2nd.). Oxford.
Lua i Stíl Chicago (17ú heag.)Singer, Peter. Marx: A Very Short Introduction. 2nd. Oxford, 2018.
Lua MLA (9ú heag.)Singer, Peter. Marx: A Very Short Introduction. 2nd. Oxford, 2018.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.