Bid of H.H. Peterson for Laying Concrete Pavement, Imperial County, California: Brawley to Holtville Route July 29, 1920
Budget: Imperial County Highways - New River Fill 1920-21
Cost Sheet: Imperial County Highways - Calezico to El Centro Road n.d.
Imperial County Highways, Frink Rock Quarry Costs 1920-21
Cost Sheets: Imperial County HIghways n.d.
Report of the Imperial County Highway Commission January 1, 1920-June 20, 1921
Report: Imperial County Highway Commission January 21, 1921
Imperial County Grand Jury Audit of Imperial County Highway Commission, Conducted by J.A. Wagner, CPA, El Centro September 9, 1922