Subgrade soil exhibit of the Bureau of Public Roads, United States Department of Agriculture.
Subtitle: Sixth Congress of the Permanent International Association of Road Congresses, Washington, 1930.
Contributors: Permanent International Association of Road Congresses.
Publisher: U.S. Govt. Print. Off.
Published: 1930
Place of publication: [Washington
Language: eng
Number of pages: 32
Subjects: Soils.; Roads -- United States.
Notes: Cover title.