1. Editorial comments;Ingelfinger,1964
2. Treatment of chronic portalsystemic encephalopathy with lactulose;Bircher;Lancet,1966
3. Ammonia absorption from the human colon. The role of non-ionic diffusion;Castell;Gastroenterology,1971
4. The mechanism of action of lactulose in portal-systemic encephalopathy. Non-ionic diffusion of ammonia in the canine colon;Bircher;Rev Eur Etud Clin Biol,1971
5. Ammonia production by intestinal bacteria;Vince;Gut,1973