Perkin, H. J. (1970). History: An introduction for the intending student. Routledge & K. Paul.
Lua i Stíl Chicago (17ú heag.)Perkin, Harold James. History: An Introduction for the Intending Student. London: Routledge & K. Paul, 1970.
Lua MLA (9ú heag.)Perkin, Harold James. History: An Introduction for the Intending Student. Routledge & K. Paul, 1970.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.