Callander, J. (1904) “Notice of a Stone Mould for Casting Flat Bronze Axes and Bars found in the Parish of Insch, Aberdeenshire; with Notes on the occurrence of Flat Axe Moulds in Europe”, Proceedings of the Society of Antiquaries of Scotland, 38, pp. 487-505. doi: 10.9750/PSAS.038.487.505.