@inproceedings{sparsenonnegativematrixlanguagemodeling,
  title = {Sparse Non-negative Matrix Language Modeling},
  author = {Joris Pelemans and Noam Shazeer and Ciprian Chelba},
  year = {2016},
  booktitle = {TACL 2016 1},
  url = {https://aclanthology.org/Q16-1024},
}