Outcome in patients with subarachnoid haemorrhage and negative angiography according to pattern of haemorrhage an computed tomography. - Rinkel,G.JE.; Wijdicks,E.FM.; Kasan,D.; Kienstra,G.EM.; Franke,C.L.; Hageman,L.M.; Vermeulen,M.; Gijn,J van. (Lancet, 1991)