Abstract

References
1.
Birrell
J F
. (1952 ) Proc. R. Soc. Med.
45 , 360
2.
Franklin
A W
. (1952 ) Proc. R. Soc. Med.
45 , 358
3.
Holinger
P H
. (1961 ) J. Laryng.
75 , 1
4.
Wilson
T G
. (1952 ) Proc. R. Soc. Med.
45 , 355
