About Dúngal mac Cinaeda
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From Wikipedia: The only event reported in Kenneth's reign is the killing of Dúngal mac Cináeda by Gille Coemgáin mac Cináeda, by the Annals of the Four Masters s.a. 999. It is not certain that this refers to events in Scotland, and whether one or both were sons of this Kenneth, or of Kenneth II of Scotland, or some other person or persons, is not known. http://www.ucc.ie/celt/published/T100005B/index.html