Citazione Stile APA (7a Edizione)
English As a Second Language: A New Approach for the 21st Century : Student Leaflets Lessons 21-40. ModuLearn.
Citazione stile Chigago Style (17a edizione)
English As a Second Language: A New Approach for the 21st Century : Student Leaflets Lessons 21-40. California, EUA: ModuLearn.
Citatione MLA (9a ed.)
English As a Second Language: A New Approach for the 21st Century : Student Leaflets Lessons 21-40. ModuLearn.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.