Spradley, L. H. (1985). Surveying and navigation for geophysical exploration. International Human Resources Development Corp..
Chicago-viite (17. p.)Spradley, L. Harold. Surveying and Navigation for Geophysical Exploration. Boston: International Human Resources Development Corp., 1985.
MLA-viite (8. p.)Spradley, L. Harold. Surveying and Navigation for Geophysical Exploration. International Human Resources Development Corp., 1985.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.