Traps.
Mason, O. T. American Anthropologist, 1900, pp. 657 ff. A general discussion. 1900.
Tubes.
Read, M. C. American Antiquarian, vol. 2, p. 53. 1879.
Turquoise.
Pepper, G. H. American Anthropologist, vol. 7, n. s., pp. 194 ff. Pueblo Bonito. 1905.
Wampum.
Parkman, F. The Jesuits in North America, p. xxxi.
Holmes, W. H. Report of the Bureau of Ethnology, 2, pp. 235 ff. 1880–81.
Adams, W. W. The Archæologist, vol. 1, p. 83. 1893.