Transportation Planning and Programming Division (n.d.). "State Highway Loop No. 635". Highway Designation Files. Texas Department of Transportation. Retrieved December 22, 2022.
txdot.gov
Transportation Planning and Programming Division (n.d.). "Highway Designations Glossary". Texas Department of Transportation. Archived from the original on July 10, 2022. Retrieved May 20, 2020.
Transportation Planning and Programming Division (n.d.). "Highway Designations Glossary". Texas Department of Transportation. Archived from the original on July 10, 2022. Retrieved May 20, 2020.