Subarachnoid Hemorrhage Without Detectable Aneurysm
Stroke 24:1403-1409, Rinkel,G.J.E.,et al, 1993
Subarachnoid Hemorrhage of Unknown Etiology
JNNP 40:926, Hayward,R.D., 1977
Investigating suspected subarachnoid hemorrhage in adults
, Brown, S.C., et al,