Knowledge, S. f. t. E. o. L. (1920). One Mystery Less. New York.
Lua i Stíl Chicago (17ú heag.)Knowledge, Society for the Extension of Liberal. One Mystery Less. New York, 1920.
Lua MLA (8ú heag.)Knowledge, Society for the Extension of Liberal. One Mystery Less. New York, 1920.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.