"Appropriation, $500,000, Sunset Extension, Municipal Railway". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 16 (38). The Recorder Printing and Publishing Company: 796. September 19, 1921. Retrieved August 6, 2018.
"Appropriation, $500,000, Sunset Extension, Municipal Railway". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 16 (39). The Recorder Printing and Publishing Company: 832. September 26, 1921. Retrieved August 6, 2018.
"Sunset District Extension". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 16 (47). The Recorder Printing and Publishing Company: 994. November 21, 1921. Retrieved August 6, 2018.
"Tunnel Construction Resolution of Intention". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 17 (22). The Recorder Printing and Publishing Company: 454–458. May 31, 1922. Retrieved August 6, 2018.
"Reconsideration–Duboce Tunnel". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 17 (23). The Recorder Printing and Publishing Company: 502. June 5, 1922. Retrieved August 6, 2018.
"Appropriation, $1,500, Test Borings, Duboce Tunnel". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 17 (27). The Recorder Printing and Publishing Company: 544. July 3, 1922. Retrieved August 6, 2018.
"Presentation of Proposals: Duboce Tunnel". Journal of Proceedings: Board of Supervisors, City and County of San Francisco. 17 (38). The Recorder Printing and Publishing Company: 742–743. September 18, 1922. Retrieved August 6, 2018.
O'Shaughnessy, Michael M. (1924–1925). Report of the Bureau of Engineering (Report). Department of Public Works, City and County of San Francisco. pp. 6, 16–17. Retrieved August 6, 2018.
O'Shaughnessy, Michael M. (1925–1926). Report of the Bureau of Engineering (Report). Department of Public Works, City and County of San Francisco. p. 20. Retrieved August 6, 2018.
O'Shaughnessy, Michael M. (1927–1928). Report of the Bureau of Engineering (Report). Department of Public Works, City and County of San Francisco. pp. 26–28. Retrieved August 6, 2018.
O'Shaughnessy, Michael M. (1926–1927). Report of the Bureau of Engineering (Report). Department of Public Works, City and County of San Francisco. pp. 19–22. Retrieved August 6, 2018.
Ost, Paul J. (October 1928). "New Tunnel an Engineering Feat". The Municipal Employee. Vol. II, no. 10. pp. 12, 54. Retrieved August 6, 2018.
O'Shaughnessy, Michael M. (1928–1929). Report of the Bureau of Engineering (Report). Department of Public Works, City and County of San Francisco. p. 52. Retrieved August 6, 2018.
Ring, Vincent D. (May 1971). "V. A Second Tunnel for the Sunset"(PDF). Tunnels and Residential Growth in San Francisco, 1910 - 1930 (M.A.). University of San Francisco. pp. 118–141. Retrieved August 6, 2018.