Levy, B. N., & Hubbard, . E. (1995). Graphing calculator keystroke guide to accompany the Hubbard/Robinson algebra series. D.C. Heath.
Lua i Stíl Chicago (17ú heag.)Levy, Benjamin N., agus Elaine Hubbard. Graphing Calculator Keystroke Guide to Accompany the Hubbard/Robinson Algebra Series. Lexington, Mass.: D.C. Heath, 1995.
Lua MLA (8ú heag.)Levy, Benjamin N., agus Elaine Hubbard. Graphing Calculator Keystroke Guide to Accompany the Hubbard/Robinson Algebra Series. D.C. Heath, 1995.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.