1. Valvular defect in primary varicose veins, cause or effect;Ludbrook;Lancet,1963
2. Circulation patterns in incompetent perforating veins and in the saphenous system in primary varicose veins;Bjordal;Acta Chir. Scand.,1972
3. The results of simultaneous pressure recordings from the superficial and deep veins of the leg;Fegan;Irish J. Med. Sci.,1964
4. Sapheno-femoral valve insufficiency in varicose veins of the lower limb;Zelikovski;Angiology,1981