Heller, S. (1901). Twenty-four preludes for the piano, op. 81. G. Schirmer.
Lua i Stíl Chicago (17ú heag.)Heller, Stephen. Twenty-four Preludes for the Piano, Op. 81. New York: G. Schirmer, 1901.
Lua MLA (9ú heag.)Heller, Stephen. Twenty-four Preludes for the Piano, Op. 81. G. Schirmer, 1901.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.