Watkins, F. C. (1962). Exercises to accompany Practical English handbook. Houghton Mifflin.
Citazione stile Chigago Style (17a edizione)Watkins, Floyd C. Exercises to Accompany Practical English Handbook. Boston: Houghton Mifflin, 1962.
Citatione MLA (9a ed.)Watkins, Floyd C. Exercises to Accompany Practical English Handbook. Houghton Mifflin, 1962.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.