BibTeX

@misc{Hutchisson1977,
  author       = {Hutchisson, Don},
  howpublished = {Unpublished manuscript, Summer Institute of Linguistics Papua New Guinea Branch},
  title        = {Sursurunga counting systems},
  url          = {https://pnglanguages.sil.org/resources/archives/43575 https://www.sil.org/system/files/reapdata/74/80/75/74807579311588867650302244692203727934/Sursurunga_Counting_Systems.pdf},
  year         = {1977},
  sections     = {None}
}