Stevenson, Roland C. 2009. Tira and Otoro: Two Kordofanian grammars. Ruediger Koppe.
@book{1375_otr,
author = {Stevenson, Roland C.},
publisher = {Ruediger Koppe},
title = {Tira and Otoro: Two Kordofanian grammars},
year = {2009}
}