Cita APA (7a ed.)

Fitzhugh, K., & Fitzhugh, L. (1966). Fitzhugh PLUS program: Perceptual learning and understanding skills. Allied Educational Council.

Cita Chicago Style (17a ed.)

Fitzhugh, Kathleen, y Loren Fitzhugh. Fitzhugh PLUS Program: Perceptual Learning and Understanding Skills. Galien, Mich.: Allied Educational Council, 1966.

Cita MLA (8a ed.)

Fitzhugh, Kathleen, y Loren Fitzhugh. Fitzhugh PLUS Program: Perceptual Learning and Understanding Skills. Allied Educational Council, 1966.