Citazione Stile APA (7a Edizione)

Sommerville, I., & Sawyer, P. (1977). Requirements engineering: A good practice guide. Wiley.

Citazione stile Chigago Style (17a edizione)

Sommerville, Ian, e Pete Sawyer. Requirements Engineering: A Good Practice Guide. Chichester, Eng. ; New York ; New Delhi: Wiley, 1977.

Citatione MLA (8a ed.)

Sommerville, Ian, e Pete Sawyer. Requirements Engineering: A Good Practice Guide. Wiley, 1977.