Cita APA (7th ed.)

Knowles, M. S. (1990). The adult learner: A neglected species (4th ed.). Gulf Pub. Co.

Cita Chicago (17th ed.)

Knowles, Malcolm Shepherd. The Adult Learner: A Neglected Species. 4th ed. Houston: Gulf Pub. Co, 1990.

Cita MLA (9th ed.)

Knowles, Malcolm Shepherd. The Adult Learner: A Neglected Species. 4th ed. Gulf Pub. Co, 1990.