APA

United States, Cowan S. H. & Cary G. (1918). Federal operation of transportation systems: extracts from hearings on H.R. 8172. [Washington, D.C.]: .

Chicago

United States, Cowan S H and Cary Graddy. 1918. Federal operation of transportation systems: extracts from hearings on H.R. 8172. [Washington, D.C.]: .

Harvard

United States, Cowan S. H. and Cary G. (1918). Federal operation of transportation systems: extracts from hearings on H.R. 8172. [Washington, D.C.]: .

MLA

United States, Cowan S H and Cary Graddy. Federal operation of transportation systems: extracts from hearings on H.R. 8172. [Washington, D.C.]: . 1918.