Zhiwen Yang and  Jingyuan Li and  Zhenkai Xie and  Jian Ling and  Jiguang Wang and  Mengliang Li,  Real-World PM, PN and NOx Emission Differences among DOC+CDPF Retrofit Diesel-, Diesel- and Natural Gas-Fueled Buses.   journal   = {International Journal of Energy and Power Engineering}, [online]. World Academy of Science, Engineering and Technology.
    August 2022, vol. 188(8). 113 - 117
    [viewed 10 May 2024]. Available from: https://publications.waset.org/pdf/10012635.