I apologize for my inappropriate language earlier.  As to the rest, like Halaqah says - not everything has to be cited, and the basic claim in my statement is about as close to "common knowledge"  as one can get.  Columbia says, for instance, that  the Bantu  "inhabit most of the continent  S of the Congo River except the extreme southwest."  The map in this article shows more or less my point.  The revert was clearly a WP:POINT violation because I was arguing with Mel on another talk page.  Would Mel revert me if I made an unsourced edit that George W. Bush is President of the United States, or that the  Earth is the third planet from the sun, too?