24 Elie Metchnikoff, The Prolongation of Life (New York: G. P. Putnam’s Sons, 1908).

25 Sherwood Gorbach, “The Discovery of Lactobacillus GG” Nutrition Today 31 (1996), 2S – 4S.

26 H. L. DuPont, “Prevention of Diarrhea by the Probiotic Lactobacillus GG” Journal ofPediatrics 134 (1999), 1–2; T. Arvola et al., “Prophylactic Lactobacillus GG Reduces Antibiotic-Associated Diarrhea in Children with Respiratory Infections: A Randomized Study”, Pediatrics 104 (1999), e64; E. Hilton et al., “Efficacy of Lactobacillus GG as a Diarrheal Preventive in Travelers”, Journal of Travel Medicine 4 (1997), 41–43; J. A. Billier et al., “Treatment of Recurrent Clostridium difficile Colitis with Lactobacillus GG” Pediatric Gastroenterology and Nutrition 21 (1995), 224–226.

27 Andrew Bruce et al., “Recurrent Urethritis in Women”, Canadian Medical Association Journal 108 (1973), 973–976; Andrew Bruce et al., “The Significance of Perineal Pathogens in Women”, Journal of Urology 112 (1974), 808–810.