Niggli, Urs and Niggli, Idda. 2008. Grammaire Élémentaire du Kassem. Ouagadougou: Summer Institute of Linguistics.
@book{sinnemakizeromarking-Niggli2008, address = {Ouagadougou}, author = {Niggli, Urs and Niggli, Idda}, publisher = {Summer Institute of Linguistics}, title = {Grammaire Élémentaire du Kassem}, year = {2008} }