Southworth, G. V. D., & Southworth, J. V. D. (1959). A work book on The story of our America (Rev. ed.). Iroquois Pub. Co..
Lua i Stíl Chicago (17ú heag.)Southworth, Gertrude Van Duyn, agus John Van Duyn Southworth. A Work Book on The Story of Our America. Rev. ed. Syracuse, N.Y.: Iroquois Pub. Co., 1959.
Lua MLA (8ú heag.)Southworth, Gertrude Van Duyn, agus John Van Duyn Southworth. A Work Book on The Story of Our America. Rev. ed. Iroquois Pub. Co., 1959.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.