@ARTICLE{8340224,
  author={Shi, Zhenwei and Shi, Tianyang and Zhou, Min and Xu, Xia},
  journal={IEEE Transactions on Geoscience and Remote Sensing}, 
  title={Collaborative Sparse Hyperspectral Unmixing Using  $l_{0}$  Norm}, 
  year={2018},
  volume={56},
  number={9},
  pages={5495-5508},
  doi={10.1109/TGRS.2018.2818703}}