"Robin Hahnel". Portland State University. Portland State College of Urban & Public Affairs. Archived from the original on December 15, 2018. Retrieved July 9, 2017.
"Robin Hahnel". Portland State University. Portland State College of Urban & Public Affairs. Archived from the original on December 15, 2018. Retrieved July 9, 2017.
Polich, Edward L. (1950). A history of Portland's secondary school system with emphasis on the superintendents and the curriculum (Thesis/dissertation). University of Portland. p.161. OCLC232551057.