Hereditary protein S deficiency and venous thromboembolism. A study in three dutch families - Broekmans, AW; Bertina, RM; Reinalda-Poot, J; Engesser, L; Muller, HP; Leeuw, JA; Michiels, JJ; Brommer, EJP; Briet, E (Thromb Haemostas, 1985)