Drummond, James. “Notice of a Highland Powder Horn, Having on It the Monogram of Sir George Mackenzie; With Some Remarks on Highland Costume. (The Horn, With Others of Various Kinds, Was Exhibited.)”. Proceedings of the Society of Antiquaries of Scotland 9 (November 30, 1873): 503. Accessed May 30, 2023. http://journals.socantscot.org/index.php/psas/article/view/5531.