1. ATS statement-Snowbird workshop on standardization of spirometry;American Thoracic Society;Am Rev Resp Dis,1979
2. Pulmonary Function Testing Guidelines and Controversies,1982
3. Spirometric standards for healthy nonsmoking adults;Morris;Am Rev Reap Dis,1979
4. Psychophysical bases of perceived exertion;Borg;Med Sci Sports Exerc,1982
5. Modern Factor Analysis;Harman,1967