Sheffield, L. M., & Sheffield, N. C. (1927). Swimming simplified (Rev. and enl. ed.). A. S. Barnes.
Lua i Stíl Chicago (17ú heag.)Sheffield, Lyba M., agus Nita C. Sheffield. Swimming Simplified. Rev. and enl. ed. New York: A. S. Barnes, 1927.
Lua MLA (8ú heag.)Sheffield, Lyba M., agus Nita C. Sheffield. Swimming Simplified. Rev. and enl. ed. A. S. Barnes, 1927.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.