Art in Shell of the Ancient Americans Second annual report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1880-81, pages 179-306

Ancient America, in Notes on American Archaeology

The Story of Extinct Civilizations of the West

Travels Amongst American Indians, Their Ancient Earthworks and Temples Including a Journey in Guatemala, Mexico and Yucatan, and a Visit to the Ruins of Patinamit, Utatlan, Palenque and Uxmal