Cita APA (7a ed.)

Kingsbury, R., & Wellman, G. (1990). Longman proficiency: Practice exams. Longman.

Cita Chicago Style (17a ed.)

Kingsbury, Roy, y Guy Wellman. Longman Proficiency: Practice Exams. Essex, England: Longman, 1990.

Cita MLA (8a ed.)

Kingsbury, Roy, y Guy Wellman. Longman Proficiency: Practice Exams. Longman, 1990.