Heywood, W. (1921). A history of Pisa, eleventh and twelfth centuries. Cambridge University Press.
Lua i Stíl Chicago (17ú heag.)Heywood, William. A History of Pisa, Eleventh and Twelfth Centuries. Cambridge: Cambridge University Press, 1921.
Lua MLA (9ú heag.)Heywood, William. A History of Pisa, Eleventh and Twelfth Centuries. Cambridge University Press, 1921.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.
