@inproceedings{spectrallearningofrefinementhmms,
  title = {Spectral Learning of Refinement HMMs},
  author = {Karl Stratos and Alex Rush and er and Shay B. Cohen and Michael Collins},
  year = {2013},
  booktitle = {WS 2013 8},
  url = {https://aclanthology.org/W13-3507},
}