3Yip K H, Lee F, Tam P C. Holmiumlaser lithotripsy for ureteral calculi: an outpatient procedure. J Endourol, 1998,12: 241- 246.
4Wollin T A,Razvi H A,Denstedt J D. Ientifying stone composition using infraredanalysis of filtered urine after ureteroscopic lithotripsy. J Endourol, 1999,13: 499-503.