1. Bolondi L, Bortotottì M, Santi V, Caletti T, Gaiani S, Labò G (1985) Measurement of gastric emptying time by real-time ultrasonography. Gastroenterology 89: 752–759
2. Bond JH, Levitt MD, Prentiss R (1975) Investigation of small bowel transit time in man utilizing pulmonary hydrogen (H2) measurements. J Lab Clin Med 85: 546–555
3. Desaga JF, Hixt U (1987) Sonographische Bestimmung der Magenentleerung. Ultraschall 8: 138–141
4. Dodds W, Groh W, Darweesh R, Kern M (1985) Sonographic measurement of gallbladder volume. Am J Radiol 145: 1009–1011
5. Everson GT, Bravermen DZ, Johnson ML, Kern F jr (1980) A critial evaluation of real time ultrasonography for the study of gallbladder volume and contraction. Gastroenterology 79: 40–46