Godwin, H. C. (1899). 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.). J. Wiley & sons.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)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: J. Wiley & sons, 1899.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)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. J. Wiley & sons, 1899.