Wheeler, O., & Tenggren, G. (1943). Sing for Christmas: A round of Christmas carols and stories of the carols. E.P. Dutton and Company, Inc..
Lua i Stíl Chicago (17ú heag.)Wheeler, Opal, agus Gustaf Tenggren. Sing for Christmas: A Round of Christmas Carols and Stories of the Carols. New York, N.Y.: E.P. Dutton and Company, Inc., 1943.
Lua MLA (8ú heag.)Wheeler, Opal, agus Gustaf Tenggren. Sing for Christmas: A Round of Christmas Carols and Stories of the Carols. E.P. Dutton and Company, Inc., 1943.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.