Ciuti G, Grifoni E, Pavellini A, Righi D, Livi R, Perfetto F, Abbate R, Prisco D, Pignone AM. Incidence and characteristics of asymptomatic distal deep vein thrombosis unexpectedly found at admission in an Internal Medicine setting. Thromb Res. 2012 Oct;130(4):591–5. doi: 10.1016/j.thromres.2012.05.018. PMID: 22694877.