A comparative randomized trial of heparin versus streptokinase in the treatment of acute proximal venous thrombosis: an interim report of a prospective trial - Elliot, MS; Immelman, EJ; Jeffrey, P; Benatar, SR; Funston, MR; Smith, JA; Shepstone, BJ; Ferguson, AD; Jacobs, P; Walker, W; Louw, JH (Br J Surg, 1979)