1. Folkman WS. Levels and sources of forest fire prevention knowledge of California hunters. Pacific Southwest Forest and Range Experiment Station, Berkeley, CA: USDA Forest Service; 1963. Research Paper PSW-11.
2. Folkman WS. Residents of Butte County, California: their knowledge and attitudes regarding forest fire prevention. Pacific Southwest Forest and Range Experiment, Berkeley, CA:USDA Forest Service; 1965. Research Paper PSW-25.
3. Folkman WS. “Children-with-matches” fires in the Angeles National Forest area. Berkely, California: Pacific Southwest Forest and Range Experiment Station, Berkeley, CA: USDA Forest Service; 1966. Research Note PSW-109.
4. Folkman WS. Motorists’ knowledge of the ‘No Smoking’ ordinance in southern California. Pacific Southwest Forest and Range Experiment Station, Berkeley, CA: USDA Forest Service; 1965. Research Note PSW-72.
5. Siegelman EY, Folkman WS. Youthful fire-setters: an exploratory study in personality and background. Pacific Southwest Forest and Range Experiment Station, Berkeley, CA: USDA Forest Service; 1971. Research Note PSW-230.