APA Style
Valacich, J, S., George, J, F. (2021).
Modern systems analysis and design (9th.ed).
Harlow:
Pearson Education Limited.
MLA Style
Valacich, Joseph, S.., George, Joey, F..
"Modern systems analysis and design".
9th.ed
Harlow:
Pearson Education Limited,
2021.
PDF.