Different intensities of oral anticoagulant Therapy in the treatment of proximal vein thrombosis - Hull, R; Hirsh, J; Jay, R; Carter, C; England, C Y; Gent, M; Turpie, A G G; McLoughlin, P; Dodd, M; Thomas, D; Rascob, G; Ockelford, P (N Engl J Med, 1982)