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  johnsonDFMethodVocal2020,
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  ISSN={1868-6354},
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  DOI={10.5334/labphon.196},
  number={11},
  journal={Laboratory Phonology: Journal of the Association for Laboratory Phonology},
  publisher={Ubiquity},
  author={Johnson, Keith},
  year={2020},
  month={Jul},
pages={10} }

@article{
  lobanov,
  title={Classification of Russian vowels spoken by different listeners},
  volume={49},
  DOI={10.1121/1.1912396},
  note={Citation Key: lobanov},
  journal={Journal of the Acoustical Society of America},
  author={Lobanov, Boris},
  year={1971},
pages={606–608} }

@phdthesis{
  neareyPhoneticFeatureSystems1978,
  title={Phonetic Feature Systems for Vowels},
  school={University of Alberta},
  author={Nearey, Terrance M.},
year={1978} }

@article{
  wattEvaluationTechniqueImproving2002,
  title={Evaluation of a technique for improving the mapping of multiple speakers’ vowel spaces in the F1 ~ F2 plane},
  volume={9},
  journal={Leeds Working Papers in Linguistics and Phonetics},
  author={Watt, Dominic and Fabricius, Anne},
  year={2002},
pages={159–173} }

@article{
  syrdalPerceptualModelVowel1986,
  title={A perceptual model of vowel recognition based on the auditory representation of American English vowels},
  volume={79},
  ISSN={0001-4966, 1520-8524},
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  number={4},
  journal={The Journal of the Acoustical Society of America},
  author={Syrdal, Ann K. and Gopal, H. S.},
  year={1986},
  month={Apr},
pages={1086–1100} }
