Stümke, H. F. (1998). Gay and Gray. SVD.
Lua i Stíl Chicago (17ú heag.)Stümke, Hans-Georg; Freytag. Gay and Gray. Köln: SVD, 1998.
Lua MLA (8ú heag.)Stümke, Hans-Georg; Freytag. Gay and Gray. SVD, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.