The Benson Latin American Collection of the University of Texas Libraries has rich holdings for primary research on Mesoamerica. The two key collections are those of Joaquin Garcia Icazbalceta and Genaro Garcia, both of whom were collectors of rare books and manuscripts. Both were interested in ethnohistorical materials. One of the best groups of pictorial manuscripts are the sixteenth-century examples of the Relaciones geograficas genre held by Texas, in the Garcia Icazbalceta collection.
John F. Schwaller, A Guide to Nahuatl Language Manuscripts Held in U.S. Repositories (2001), pp. 28-33, provides a lengthy description of the Benson materials, and in subsequent pages gives detailed descriptions of individual manuscripts.
See also the Handbook of Middle American Indians (1975), vol. 15, pp. 457-458, for both general and detailed descriptions of Benson holdings. Keywords for assisting with the identification of the manuscripts listed in the HMAI include: Códice Indígena, Meztitlan Calendar Wheel, Nezahualcoyyotl, Posesiones de Don Andrés, Quauhtliztactzin, Tecpatepec, Pintura, Lienzo de Tlaxcala, Veytia Calendar Wheel, Codex of Xochitepec, hernando Alvarado Tezozomoc, Imperio Azteca, Aztec manuscript, Gabriel de Castañeda, Chimalpahin, Genealogía y linaje de los señores..., tributaba, Leyes, Mendieta, Historia de los Mexicanos por sus pinturas, Origen de los Mexicanos, Motolinia, Muñoz Camargo, Oro y tesoro, Juan Bautista Pomar, Texcoco, Romances, Tecamachalco, and Alonso de Zorita. [SW]