Abstract
References
1.
Arthur
A B
Clayton
B E
Cottom
D G
Seakins
J W T
Platt
J W
. (1966 ) Lancet
i , 172
2.
Haworth
E M
Hodson
C J
Pringle
E M
Young
W F
. (1968 ) Clan. Radiol . 19 , 65