Effectiveness of Guy's stone score to predict surgical outcomes in prone versus modified supine position percutaneous nephrolithotomyFERDI, ADANARTO, INDRAWARMAN, Author information1Division of Urology, Department of Surgery, Faculty of Medicine, Gadjah Mada University, Sardjito General Hospital, Yogyakarta, IndonesiaBJU International 117:p 12-13, May 2016.Copyright © 2016 John Wiley & Sons, Ltd