(1970). Ideas and actions: A history of the Highway Research Board 1920-1970. Washington, D.C: [s.n.].
Παραπομπή Chicago StyleIdeas and Actions: A History of the Highway Research Board 1920-1970. Washington, D.C: [s.n.], 1970.
Παραπομπή MLAIdeas and Actions: A History of the Highway Research Board 1920-1970. Washington, D.C: [s.n.], 1970.
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