Optimal Duration of Oral Anticoagulant Therapy: a Randomized Trial Comparing Four Weeks With Three Months of Warfarin in Patients With Proximal Deep Vein Thrombosis - Levine, MN; Hirsh, J; Gent, M; Turpie, AG; Weitz, J; Ginsberg, J; Geerts, W; LeClerc, J; Neemeh, J; Powers, P (Thromb Haemost, 1995)