A comprehensive bibliography dealing with the archaeology and ethno-history of Mesoamerica and the north of Mexico has been prepared by Ignacio Bernal, Bibliografia de arqueología y etnografía de Mesoamérica y norte de México, 1514–1960 (Mexico, D.F., 1962). Descriptions of many of the extant indigenous sources, i.e. pictorial manuscripts and others in the native historical tradition, are provided by John B. Glass, Donald Robertson, Charles Gibson and Henry B. Nicholson in a series of articles in volumes 14 and 15 (1975), edited by Howard F. Cline, of the Handbook of Middle American Indians, ed. Robert Wauchope, 16 vols. (Austin, Tex., 1964–76). An invaluable reference work, giving a chronology of Nahuatl scholarship from 1546 to 1980 and a catalogue of Nahuatl printed works (some 2, 961 items), has been assembled by Ascensión H. de León-Portilla, Tepuztlahcuilolli: Impresos en náhuatl: Historia y bibliografía, 2 vols. (Mexico, D.F., 1988). An indispensable guide to Nahuatl manuscripts in the Newberry Library, Chicago, the Latin American Library of Tulane University and the Bancroft Library, University of California at Berkeley, is provided by John Frederick Schwaller in Estudios de cultura náhuatl, 18 (1986), 315–83. On Nahuatl manuscripts in the John Carter Brown Library, Providence, Rhode Island, and the Nettie Lee Benson Latin American Collection at the University of Texas at Austin, see Estudios de cultura náhuatl, 21 (1991), 311–38.