Heckert, J. B., & Willson, J. D. (1963). Controllership (2nd ed.). Ronald Press.
Lua i Stíl Chicago (17ú heag.)Heckert, J. Brooks, agus James D. Willson. Controllership. 2nd ed. New York: Ronald Press, 1963.
Lua MLA (8ú heag.)Heckert, J. Brooks, agus James D. Willson. Controllership. 2nd ed. Ronald Press, 1963.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.