Cita APA (7th ed.)

Hobbs, G. M. (1972). Practical mathematics (3rd.ed.). American technical.

Cita Chicago (17th ed.)

Hobbs, Glen M. Practical Mathematics. 3rd.ed. Illinois: American technical, 1972.

Cita MLA (9th ed.)

Hobbs, Glen M. Practical Mathematics. 3rd.ed. American technical, 1972.