@inproceedings{libovicky-fraser-2021-lmu,
    title = "The {LMU} {M}unich Systems for the {WMT}21 Unsupervised and Very Low-Resource Translation Task",
    author = "Libovick{\'y}, Jind{\v{r}}ich  and
      Fraser, Alexander",
    editor = "Barrault, Loic  and
      Bojar, Ondrej  and
      Bougares, Fethi  and
      Chatterjee, Rajen  and
      Costa-jussa, Marta R.  and
      Federmann, Christian  and
      Fishel, Mark  and
      Fraser, Alexander  and
      Freitag, Markus  and
      Graham, Yvette  and
      Grundkiewicz, Roman  and
      Guzman, Paco  and
      Haddow, Barry  and
      Huck, Matthias  and
      Yepes, Antonio Jimeno  and
      Koehn, Philipp  and
      Kocmi, Tom  and
      Martins, Andre  and
      Morishita, Makoto  and
      Monz, Christof",
    booktitle = "Proceedings of the Sixth Conference on Machine Translation",
    month = nov,
    year = "2021",
    address = "Online",
    publisher = "Association for Computational Linguistics",
    url = "https://preview.aclanthology.org/fix-sig-urls/2021.wmt-1.105/",
    pages = "989--994",
    abstract = "We present our submissions to the WMT21 shared task in Unsupervised and Very Low Resource machine translation between German and Upper Sorbian, German and Lower Sorbian, and Russian and Chuvash. Our low-resource systems (German{\ensuremath{\leftrightarrow}}Upper Sorbian, Russian{\ensuremath{\leftrightarrow}}Chuvash) are pre-trained on high-resource pairs of related languages. We fine-tune those systems using the available authentic parallel data and improve by iterated back-translation. The unsupervised German{\ensuremath{\leftrightarrow}}Lower Sorbian system is initialized by the best Upper Sorbian system and improved by iterated back-translation using monolingual data only."
}