Cita APA (7th ed.)
Welch, C. L., & Peter, G. M. (1985). Elementary algebra. Scott, Foresman.
Cita Chicago (17th ed.)
Welch, C. Lee, i Gilbert M. Peter. Elementary Algebra. Glenview, Ill.: Scott, Foresman, 1985.
Cita MLA (9th ed.)
Welch, C. Lee, i Gilbert M. Peter. Elementary Algebra. Scott, Foresman, 1985.
Atenció: Aquestes cites poden no estar 100% correctes.