https://www.sil.org/resources/archives/32299
https://www.sil.org/resources/archives/32282
https://www.sil.org/resources/archives/3698
Available: http://www.sil.org/silesr/2008/silesr2008-008.pdf. A paper copy may be made from the pdf
https://www.sil.org/resources/archives/47872
https://www.sil.org/resources/archives/70856