@article{chi-geman-1998-estimation,
    title = "Estimation of Probabilistic Context-Free Grammars",
    author = "Chi, Zhiyi  and
      Geman, Stuart",
    editor = "Hirschberg, Julia",
    journal = "Computational Linguistics",
    volume = "24",
    number = "2",
    year = "1998",
    address = "Cambridge, MA",
    publisher = "MIT Press",
    url = "https://preview.aclanthology.org/fix-sig-urls/J98-2005/",
    pages = "299--305"
}