Foreman, Velma M. 1974. Grammar of Yessan-Mayo. (Language Data: Asian-Pacific Series, 4.) Ukarumpa: Santa Ana: Summer Institute of Linguistics. iv+304pp.
http://www.sil.org/acpub/repository/10677_front.pdf, http://www.sil.org/acpub/repository/10677.pdf
@book{reesinkgive-80968,
address = {Ukarumpa},
author = {Foreman, Velma M.},
number = {4},
pages = {iv+304},
publisher = {Santa Ana: Summer Institute of Linguistics},
series = {Language Data: Asian-Pacific Series},
title = {Grammar of Yessan-Mayo},
url = {http://www.sil.org/acpub/repository/10677_front.pdf, http://www.sil.org/acpub/repository/10677.pdf},
volume = {4},
year = {1974}
}