Fischel, W. J. (1964). William Popper (1874-1963) and his contribution to islamic scholarship: In memoriam / by Walter J. Fischel.
Lua i Stíl Chicago (17ú heag.)Fischel, Walter J. William Popper (1874-1963) and His Contribution to Islamic Scholarship: In Memoriam / by Walter J. Fischel. 1964.
Lua MLA (8ú heag.)Fischel, Walter J. William Popper (1874-1963) and His Contribution to Islamic Scholarship: In Memoriam / by Walter J. Fischel. 1964.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.