Hereditary protein S deficiency and venous thrombo-embolism: a study in three Dutch families - Broekmans, A W; Bertina, R M; Reinalda-Poot, J; Engesser, L; Muller, H P; Leeuw, J A; Michiels, J J; Brommer, E J P; Briet, E (Thromb Haemostas, 1985)