(Ex parte 171)
Subtitle: rules, standards and instructions for installation, inspection, maintenance, and repair of automatic block signal systems, interlocking, traffic control systems, automatic train stop, train control and cab signal systems and other similar appliances, methods and systems, effective October 1, 1950.
Publisher: U.S. Govt. Print. Off.
Published: 1950
Place of publication: [Washington
Language: eng
Number of pages: 48
Subjects: Railroads -- Signaling.