Don't forget the first publication on the subject. It is the seminal piece and includes several examples of kaskara even though he calls them of Hausa origin.
Briggs, Lloyd Cabot. "European Blades in Tuareg Swords and Daggers." The Journal of the Arms & Armour Society (June 1965), pp. 53–54.
I don't know where to get a copy other than via inter-library loan or perhaps via on-line sale. Maybe JAAS has a reprint.
Also, on Kaskara Terminology by Iain Norman:
http://iainnorman.com/essays/2014/03...a-terminology/
I've no doubt missed some important sources, but you get the idea of the scope of valuable references.
Ed