Tolong jelaskan mengenai Sumber dari Hieronimus (putra Karl Martell)

Medieval Lands Project, Family of Hieronymus

Settipani, Christian, La préhistoire des Capétiens 481-987, 1ère partie, Mérovingiens, Carolingiens et Robertiens, Broché, 1993

Murray, J., A Dictionary of Christian Biography, Literature, Sects and Doctrines: Being a Continuations of the Dictionary of the Bible, Forgotten Books, 1882 (available on Google Books)