@book{2012tomomisatoainugochosashiryonodetabesukanikansurukiso,
  title = {Ainugo chōsa shiryō no dētabēsu-ka ni kansuru kisoteki kenkyū},
  author = {Tomomi Satō},
  year = {2012},
  url = {https://openlibrary.org/works/OL23136516W}
}