APA Style
Holtz, R, D, (, D., Kovacs, W, D. (1981).
An introduction to geotechnical engineering .
Englewood Cliffs, N.J:
Prentice-Hall.
MLA Style
Holtz, R., D., (Robert, D.)., Kovacs, William, D.,.
"An introduction to geotechnical engineering".
Englewood Cliffs, N.J:
Prentice-Hall,
1981.
Books.