M. Maciejewski, K. Piestrzeniewicz, R. Jaszewski, A. Bielecka-Dabrowa, and J. H. Goch, “Sources of Thromboembolism in Patients with Correctly Functioning Mechanical Valves: A Single-Center Transesophageal Echocardiographic Study”, HSF, vol. 14, no. 3, pp. E149-E156, Jun. 2011.