1. BUSKIRK , E. R. , KOLLIAS , J. , and HODGSON , J. L. , 1972 , The effects on pulmonary functions of work postures and work intensities common to coal mining operations . Contract No. CPE-R-7O-NEG-0043, U.S. Dept. of Health, Education and Welfare , National Institute for Occupational Safety and Health .
2. BUSKIRK , E. R. , NICHOLAS , W. G. , and HODGSON , J. L. , 1975 , Measurement of work metabolism, a use of cardiorespiratory parameters for estimating metabolic heat production in hot environments . Contract No. HSM-99-72-70, U.S. Dept. of Health, Education and Welfare , National Institute for Occupational Safety and Health .