Cita APA (7a ed.)

Farrell, M. A., & Farmer, W. A. (1980). Systematic instruction in mathematics for the middle and high school years. Addison-Wesley Publishing Company.

Cita Chicago Style (17a ed.)

Farrell, Margaret A., y Walter A. Farmer. Systematic Instruction in Mathematics for the Middle and High School Years. Reading [etc.]: Addison-Wesley Publishing Company, 1980.

Cita MLA (9a ed.)

Farrell, Margaret A., y Walter A. Farmer. Systematic Instruction in Mathematics for the Middle and High School Years. Addison-Wesley Publishing Company, 1980.