The helmet bears traces of the armorer's mark, an M beneath a crescent, possibly that of the Flemish armorer Guillem Margot, who worked for the Hapsburg court and was active in Brussels from 1505 to 1520.
Marking: Marked with a Roman M beneath a crescent.
The Metropolitan Museum of Art, Stephen V. Grancsay, and Carl Otto von Kienbusch. The Bashford Dean Collection of Arms and Armor in the Metropolitan Museum of Art. Portland, Maine: Southworth Press for the Armor and Arms Club of New York City, 1933. p. 129, no. 44, pl. IV.
Blacker, Irwin R. Cortes and the Aztec Conquest. 1st ed. New York: American Heritage Pub. Co.: book trade and institutional distribution by Harper & Row, 1965. p. 28 (our object shown with general comments; the two groups of credit lines for Riggs & Bashford Dean Memorial Collection have been confused).
Blair, Claude. "The Emperor Maximilian's Gift armour to King Henry VIII and the Silvered and Engraved Armour at the Tower of London." Archaeologia, or, Miscellaneous Tracts Relating to Antiquity 99 p. 37, pl. XIV a, b.
Terjanian, Pierre. "The King and the Armourers of Flanders." In Henry VIII: Arms and the Man, 1509–2009, edited by Graeme Rimer, Thom Richardson, and J. P. D. Cooper. Leeds: Royal Armouries, 2009. pp. 156, 159.