1. Amberson, J. B.: Aspiration bronchopneumonia. Int. Clin.3, 126–138 (1937)
2. American Thoracic Society: Definitions and classification of chronic bronchitis, asthma and pulmonary emphysema. Am. Rev. Respir. Dis.85, 762–767 (1962)
3. Barrett-Connor, E.: The nonvalue of sputum culture in the diagnosis of pneumococcal pneumonia. Am. Rev. Respir. Dis.103, 845–848 (1971)
4. Bartlett, J. G., Brewer, N. S., Ryan, K. J.: CUMITECH7 — Laboratory diagnosis of lower respiratory tract infections. Washington, D. C.: American Society for Microbiology, September 1978
5. Bartlett, J. G., Finegold, M.: Bacteriology of expectorated sputum with quantitative culture and wash technique compared to transtracheal aspirates. Am. Rev. Respir. Dis.117, 1019–1027 (1978)