Hal, J. a. (1972). Forest fuels, prescribed fire, and air quality. Pacific Northwest Forest and Range Experiment Station Forest Service U.S. Department of Agriculture Portland.

Hal, J. alfred. Forest Fuels, Prescribed Fire, and Air Quality. Oregon: Pacific Northwest Forest and Range Experiment Station Forest Service U.S. Department of Agriculture Portland, 1972.

Hal, J. alfred. Forest Fuels, Prescribed Fire, and Air Quality. Pacific Northwest Forest and Range Experiment Station Forest Service U.S. Department of Agriculture Portland, 1972.