W. M. Mackenzie, “Some Stray Inscriptions - (1) Runes on Standing Stone at Oykell Bridge; (2) on Bracket at Gleneagles; (3) on the Kindrochit Brooch; (4) the Atholl Motto; (5) Two Carved Stones of the Urquharts of Cromarty”, PSAS, vol. 61, pp. 173–191, Nov. 1927.