Gaya APA
O'leary, T., Williams, B, K. (1989).
Computers and information systems (2nd ed).
California:
The Benjamin/Cummings Publishing Company.
Gaya MLA
O'leary, T.J.., Williams, Brian, K..
"Computers and information systems".
2nd ed
California:
The Benjamin/Cummings Publishing Company,
1989.
Text.