@article{nakamon_kitirattrakarn_lojanapiwat_2013,  title={Outcomes of percutaneous nephrolithotomy: Comparison of elderly and younger patients},  volume={39},  ISSN={1677-5538},  url={https://doi.org/10.1590/S1677-5538.IBJU.2013.05.12},  DOI={10.1590/S1677-5538.IBJU.2013.05.12},  number={5},  journal={International braz j urol},  publisher={Sociedade Brasileira de Urologia},  author={Nakamon, T. and Kitirattrakarn, P. and Lojanapiwat, B.},  year={2013},  month={Sep},  pages={692–701} }