Matsuura K, Imamaki M, Ishida A, Shimura H, Miyazaki M. The effect of preoperative aspirin administration on postoperative level of von Willebrand factor in off-pump coronary artery bypass surgery. Heart Vessels. 2009 May;24(3):169–74. doi: 10.1007/s00380-008-1105-2. PMID: 19466516.