Godwin, H. C. (1894). Railroad engineers' field-book and explorers' guide: Especially adapted to the use of railroad engineers on location and construction and to the needs of the explorer in making exploratory surveys (2nd, rev. ed.). Wiley.
Chicago-referens (17:e uppl.)Godwin, H. C. Railroad Engineers' Field-book and Explorers' Guide: Especially Adapted to the Use of Railroad Engineers on Location and Construction and to the Needs of the Explorer in Making Exploratory Surveys. 2nd, rev. ed. New York: Wiley, 1894.
MLA-referens (8:e uppl.)Godwin, H. C. Railroad Engineers' Field-book and Explorers' Guide: Especially Adapted to the Use of Railroad Engineers on Location and Construction and to the Needs of the Explorer in Making Exploratory Surveys. 2nd, rev. ed. Wiley, 1894.