Mann, L.M. 1904. Notes (1) on Two Tribula or Threshing-Sledges, having their under surfaces studded with rows of chipped flints, for threshing corn on a threshing-floor, from Cavalla in European Turkey, now presented to the Museum; and (2) on Primitive Implements and Weap. Proceedings of the Society of Antiquaries of Scotland. 38, (Nov. 1904), 506–519. DOI:https://doi.org/10.9750/PSAS.038.506.519.