Libby, H. W., & Libby, H. W. (1949). Standard highway spiral. Oregon: Oregon State Highway Commission.
Chicago Style CitationLibby, H. W., and H. W. Libby. Standard Highway Spiral. Oregon: Oregon State Highway Commission, 1949.
MLA CitationLibby, H. W., and H. W. Libby. Standard Highway Spiral. Oregon: Oregon State Highway Commission, 1949.
Warning: These citations may not always be 100% accurate.