1. (1) Bartlett, J.G., N. Moon, T.W. Chang, N. Taylor, and A.B. Onderdonk. 1978. Role of Clostridium difficile in antibiotic-associated pseudomembranous colitis. Gastroenterology 75: 778-782.
2. (2) Bryson, V., and W. Szybalski. 1952. Microbial selection. Science 116: 45-51.
3. (3) Chida, T., K. Ishizu, K. Fukuda, and R. Nakaya. 1977. Susceptibility of anaerobic bacteria to a new semisynthetic penicillin, T-1220, and related drugs. J. Clin. Exper. Med.(Tokyo) 101: 889-891 (in Japanese).
4. (4) Chida, T., H. Shibaoka, H. Sagara, R. Nakaya, and K. Nakagawa. 1983. The effect of a new cephalosporin, cefoperazone, administered intravenously on human fecal flora. Chemotherapy (Tokyo) 31: 920-926 (in Japanese with English summary).
5. (5) Colombel, J.F., A. Cortot, C. Neut, and C. Romond. 1987. Yoghurt with Bifidobacterium longum reduces erythromycin-induced gastrointestinal effects. Lancet i: 43.