Gaya APA

Hughes, C, J, ;, A, T, W, ;, G, M. (1984). Essential arithmetic (ed. 4). California: WADSWORTH COMPANY.

Gaya MLA

Hughes, C.L., Johnston, ;, Alden, T., Wilis, ;, Gale, M.. "Essential arithmetic". ed. 4 California: WADSWORTH COMPANY, 1984. Text.