Papurau Robert Roberts,1934-1954, gan gynnwys llythyrau, nodiadau, llyfrau lloffion a defnyddiau pellach yn ymwneud â'i waith ar hanes a llenyddiaeth Gogledd Cymru, ac ar Absalom Fardd. = Papers of Robert Roberts, 1934-1954, comprising letters, notes, scrapbooks and other material relating to his work on the history and literature of North Wales, and to Absalom Fardd.