@article{ref1, author = "A. Kansy and T. Ebels and C. Schreiber and Z. Tobota and B. Maruszewski", title = "Association of Center Volume With Outcomes: Analysis of Verified Data of European Association for Cardio-Thoracic Surgery Congenital Database", year = 2014, journal = "The Annals of Thoracic Surgery", publisher = "Elsevier", volume = 98, number = 6, pages = "2159-2164", month = "Dec", doi = "10.1016/j.athoracsur.2014.07.065", url = "http://dx.doi.org/10.1016/j.athoracsur.2014.07.065" }