APA
(1968). ROUTE MARKER SIGNS FOR NATIONAL HIGHWAYS. : INDIAN ROADS CONGRESS.
Chicago
1968. ROUTE MARKER SIGNS FOR NATIONAL HIGHWAYS. : INDIAN ROADS CONGRESS.
Harvard
(1968). ROUTE MARKER SIGNS FOR NATIONAL HIGHWAYS. : INDIAN ROADS CONGRESS.
MLA
ROUTE MARKER SIGNS FOR NATIONAL HIGHWAYS. : INDIAN ROADS CONGRESS. 1968.