APA

Johnson R. B., Johnson R. B. & DeGraff J. V. (1988). Principles of engineering geology. New York [u.a.]: Wiley.

Chicago

Johnson Robert B, Johnson Robert Britten and DeGraff Jerome V. 1988. Principles of engineering geology. New York [u.a.]: Wiley.

Harvard

Johnson R. B., Johnson R. B. and DeGraff J. V. (1988). Principles of engineering geology. New York [u.a.]: Wiley.

MLA

Johnson Robert B, Johnson Robert Britten and DeGraff Jerome V. Principles of engineering geology. New York [u.a.]: Wiley. 1988.