Yansi language

Yans (Yanzi, Songo) is a Bantu language spoken in the Democratic Republic of Congo. 
There are six language varieties Guthrie classified as Bantu B.85 (Yans). According to Nurse (2003), most belong to the Yaka language, but one or two are assigned to the Boma–Dzing languages (ex-Yanzi); he does not say which ones.
Maho (2009) notes that the Tsong variety of Yansi is the unclassified "Songo" language of "Ethnologue" and is the one that does not belong with the rest. Ehret (2009), however, retains most varieties in B.80 and classifies only "Yanz Kimatu" as Yaka. The six Guthrie varieties are the following: