Abstract

References
1.
Lee
J A H
Morrison
S L
Morris
J N
(1957 ) Lancet
ii , 785
2.
Martin
F M
Last
J M
Stanley
G R
(1967 ) Brit. J. med. Educat . (in press)
3.
Peterson
O L
Andrews
L P
Spain
R S
Greenberg
B G
(1956 ) J. Med. Educ . 31 , No. 12 , Part 2
