Melzi d'Eril, Gianvico, Adriano Anesi, Vittoria Rizzo, et al. "Biological Variation in Protein C, Protein S and Antithrombin Concentrations in Plasma of Healthy Subjects" Clinical Chemistry and Laboratory Medicine, 35.4 (2009): 257-260. Retrieved 20 May. 2013, from doi:10.1515/cclm.1997.35.4.257

Melzi d'Eril, G., Anesi, A., Rizzo, V., et al. (2009). Biological Variation in Protein C, Protein S and Antithrombin Concentrations in Plasma of Healthy Subjects. Clinical Chemistry and Laboratory Medicine, 35(4), pp. 251-349. Retrieved 20 May. 2013, from doi:10.1515/cclm.1997.35.4.257

Melzi d'Eril, Gianvico, Adriano Anesi, Vittoria Rizzo, et al. 2009. Biological Variation in Protein C, Protein S and Antithrombin Concentrations in Plasma of Healthy Subjects. Clinical Chemistry and Laboratory Medicine. 35(4): 251-349. Retrieved 20 May. 2013, from doi:10.1515/cclm.1997.35.4.257