Greg, W. W. (1976). The calculus of variants: An essay on textual criticism. Norwood Editions.
Lua i Stíl Chicago (17ú heag.)Greg, W. W. The Calculus of Variants: An Essay on Textual Criticism. [s.l.]: Norwood Editions, 1976.
Lua MLA (8ú heag.)Greg, W. W. The Calculus of Variants: An Essay on Textual Criticism. Norwood Editions, 1976.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.