Herubin, C. A. (1991). Principles of surveying (4th ed.). Prentice Hall.
Lua i Stíl Chicago (17ú heag.)Herubin, Charles A. Principles of Surveying. 4th ed. Englewood Cliffs, N.J.: Prentice Hall, 1991.
Lua MLA (9ú heag.)Herubin, Charles A. Principles of Surveying. 4th ed. Prentice Hall, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.