Mauger (I?), tenant in Yorks 1086 of among others William de Percy; either this Mauger (I?) or another person of the same name (Mauger (II?)), possibly Mauger I?)'s son, witnessed a charter of Alan de Percy temp. Henry I; had [a son or daughter], with a younger son [Robert]. [Burke's Peerage]
Note: Because of the date spans, I believe there was a Mauger I & II.