Abstract

References
1.
Benson
P F
Joseph
M C
. (1961 ) Brit. med. J.
i , 102
2.
Earn
A A
Panner
D W
. (1950 ) J. Obstet. Gynæc. Brit. Emp.
57 , 442
3.
Froehlich
L A
Fujikura
T
Fisher
P
. (1971 ) Obstet. and Gynec.
37 , 51
4.
Mandelbaum
B
Ross
M
Riddle
C B
. (1969 ) Obstet. and Gynec.
34 , 335
