Abstract

References
1.
Chears
W C
Ashworth
C T
, (1961 ) Gastroenterology
41 , 129 .
2.
Fisher
E R
, (1962 ) J. Amer. med. Ass.
181 , 396 .
3.
Watson
J H L
Haubrich
W S
, (1964 ) Henry Ford Hosp. Bull.
12 , 421 .
4.
Yardley
J H
Hendrix
T R
, (1961 ) Bull. Johns Hopk. Hosp.
109 , 80 .
