Efird, J. T., W. T. O’Neal, S. W. Davies, J. B. O’Neal, W. R. Chitwood, T. B. Ferguson, and A. P. Kypson. “Operative Status and Survival After Coronary Artery Bypass Grafting”. The Heart Surgery Forum, vol. 17, no. 2, May 2014, pp. E82-E90, doi:10.1532/HSF98.2013310.