Sommerville, I., & Sawyer, P. (1977). Requirements engineering: A good practice guide. Wiley.
Dyfyniad Arddull ChicagoSommerville, Ian, and Pete Sawyer. Requirements Engineering: A Good Practice Guide. Chichester, Eng. ; New York ; New Delhi: Wiley, 1977.
Dyfyniad MLASommerville, Ian, and Pete Sawyer. Requirements Engineering: A Good Practice Guide. Wiley, 1977.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.