Gaya APA

Valacich, J, S., George, J, F. (2021). Modern systems analysis and design (Edisi 9). Harlow, United Kingdom: Pearson Education Limited.

Gaya MLA

Valacich, Joseph, S.., George, Joey, F.. "Modern systems analysis and design". Edisi 9 Harlow, United Kingdom: Pearson Education Limited, 2021. Buku.