APA
Groff J. R. &. W. P. N., . (1988). Understanding Unix. Tech Publications, Singapore: .
Chicago
Groff James R & Weinberg Pail N, . 1988. Understanding Unix. Tech Publications, Singapore: .
Harvard
Groff J. R. &. W. P. N., . (1988). Understanding Unix. Tech Publications, Singapore: .
MLA
Groff James R & Weinberg Pail N, . Understanding Unix. Tech Publications, Singapore: . 1988.