Inner Mongolia Baotou Vocational and Technical College, Baotou 014030, Inner Mongolia, China;
Inner Mongolia Baotou Vocational and Technical College, Baotou 014030, Inner Mongolia, China;
Inner Mongolia Baotou Vocational and Technical College, Baotou 014030, Inner Mongolia, China;
Inner Mongolia Baotou Vocational and Technical College, Baotou 014030, Inner Mongolia, China;