Polytechnic High School – Cancer Related to Landfill: Letter from DWP Employees, 1999 October 25, id17698, Box: 42, Folder: 9. Tom Hayden Belmont Learning Complex Investigation Collection, URB-BLC. Special Collections & Archives. https://findingaids.csun.edu/repositories/2/archival_objects/91869 Accessed June 10, 2026.