Effect of respiratory muscle training in patients with stable chronic obstructive pulmonary disease: A systematic review and meta-analysis oleh Zhongjie Huang, Zhibin Li, Meihao Yan, Jianming Zheng, Wencheng Huang, Liyue Hong, Qiuxiang Lu, Limin Liu, Xincheng Huang, Hongtao Fan, Weiping Su, Xiaoping Huang, Xiaoyan Wu, Zhixiong Guo, Caiting Qiu, Zhaodi Zhao, Yuancheng Hong