APA
Association of American Railroads, American Railway Association & Association of American Railroads. (1927). American railway signalling principles and practices. New York: .
Chicago
Association of American Railroads, American Railway Association and Association of American Railroads. 1927. American railway signalling principles and practices. New York: .
Harvard
Association of American Railroads, American Railway Association and Association of American Railroads. (1927). American railway signalling principles and practices. New York: .
MLA
Association of American Railroads, American Railway Association and Association of American Railroads. American railway signalling principles and practices. New York: . 1927.
