SAKAKIBARA, R., TSUNOYAMA, K., HOSOI, H., TAKAHASHI, O., SUGIYAMA, M., KISHI, M., OGAWA, E., TERADA, H., UCHIYAMA, T. and YAMANISHI. Influence of Body Position on Defecation in Humans // Department of Internal Medicine, Division of Neurology, Sakura Medical Center, Toho University, Sakura, Japan, 16 април 2010. Посетен на 11 януари 2010. (на английски)