Endangered Languages Catalogue Project. Compiled by research teams at University of Hawai'i Mānoa and Institute for Language Information and Technology (LINGUIST List) at Eastern Michigan University . (2012) ·

A sociolinguistic survey of the Sichela speech community ( pp. 20 ) . Lindfors, Anna-Lena and Woodward, Mark and Nagler, Louise (2009) · SIL electronic survey reports (SILESR), #2009-014 · SIL International