Alexander, I., & Beus-Dukic, L. (2009). Discovering requirements: How to specify products and services. Wiley.
Lua i Stíl Chicago (17ú heag.)Alexander, Ian, agus Ljerka Beus-Dukic. Discovering Requirements: How to Specify Products and Services. Chichester, West Sussex, England: Wiley, 2009.
Lua MLA (9ú heag.)Alexander, Ian, agus Ljerka Beus-Dukic. Discovering Requirements: How to Specify Products and Services. Wiley, 2009.
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