1. Bartlett R. C. V. D. Alien D. J. Blazevic C. T. Dolan V. R. Dowell T. L. Gavan S. L. Inhorn G. L. Lombard J. Matsen D. M. Melvin H. M. Sommers M. T. Suggs and B. S. West. 1978. Quality assurance in clinical microbiology p. 871-1005. In S. L. Inhorn (ed.) Quality assurance practices for health laboratories. American Public Health Association Washington D.C.
2. Ewing W. H. and W. J. Martin. 1974. Enterobacteriaceae p. 189-221. In E. H. Lennette E. H. Spaulding and J. P. Truant (ed.) Manual of clinical microbiology 2nd ed. American Society for Microbiology Washington D.C.
3. Forney J. E. J. M. Blumberg M. M. Brooke E. Eavenson R. K. Gilbert and W. Kaufmnan. 1978. Laboratory evaluation and certification p. 127-171. In S. L. Inhorn (ed). Quality assurance practices for health laboratories. American Public Health Association Washington D.C.
4. Fuchs P. C. 1982. Microbiology proficiency testing in the care of patients p. 349-409. In V. Lorian (ed.) Significance of medical microbiology in the care of patients 2nd ed. The Williams & Wilkins Co. Baltimore.
5. Five years of experience with a national external quality control program for the culture and identification of Neisseria gonorrhoeae;Griffin C. W.;J. Clin. Microbiol.,1983