Citazione Stile APA (7a Edizione)

Hopson, B. (1994). Twelve steps to success through service. Excel.

Citazione stile Chigago Style (17a edizione)

Hopson, Barrie. Twelve Steps to Success Through Service. New Delhi: Excel, 1994.

Citatione MLA (9a ed.)

Hopson, Barrie. Twelve Steps to Success Through Service. Excel, 1994.