Abstract

References
1.
Bull
J W D
. (1975 ) Neuroradiology
9 , 111 .
2.
Bull
J W D
Zilkha
K J
. (1968 ) British Medical Journal
iv , 569 .
3.
Zuppinger
A
. (1973 ) International Committee on Radiological Education , Newsletter No. 3. Mura S Chiara , Genoa .
