Cita APA (7th ed.)

Billstein, R., Libeskind, S., Lott, J., Levy, L. L., & Ritz, E. (1993). A problem solving approach to mathematics for elementary school teachers (5th ed.). Addison-Wesley.

Cita Chicago (17th ed.)

Billstein, Rick, Shlomo Libeskind, Jhonny Lott, Louis L. Levy, i Edward Ritz. A Problem Solving Approach to Mathematics for Elementary School Teachers. 5th ed. Reading, MA: Addison-Wesley, 1993.

Cita MLA (9th ed.)

Billstein, Rick, et al. A Problem Solving Approach to Mathematics for Elementary School Teachers. 5th ed. Addison-Wesley, 1993.