1. H. Lechtman in The Coming of the Age of Iron T. A. Wertime and J. D. Muhly Eds. (Yale Univ. Press New Haven CT 1980) pp. 267-334
2. ___ in Technologies of Power T. S. Henderson and P. J. Netherly Eds. (Cornell Univ. Press Ithaca NY 1993) pp. 244-280
3. I. Shimada in In Quest of Mineral Wealth-Aboriginal and Colonial Mining and Metallurgy in Spanish America vol. 33 of Geoscience and Man A. K. Craig and R. C. West Eds. (Louisiana State Univ. Baton Rouge LA 1994) pp. 41-47.
4. R. Burger and H. Lechtman in Andean Art at Dumbarton Oaks E. Boone Ed. (Dumbarton Oaks Washington DC 1996) pp. 45-86
5. W. Alva in Oro en el Antiguo Perú J. A. de Lavalle (Banco de Crédito del Perú Lima Peru 1992) pp. 17-116;