Early post-Columbian sources preserve and document aspects of indigenous literature (e.g., Ximenez's manuscript of the Popol Vuh) and writing (Diego de Landa's "Relación de las cosas de Yucatán" contained Maya calendar signs and a syllabary). As European Franciscan missionaries arrived they found that the Cholutecans used rebus principles as a way to translate information into Latin as a teaching aid for the Indians to learn Christian prayers. A number of colonial-era Aztec codices are preserved, most notably the Codex Mendoza, the Florentine Codex, and the works by Diego Durán. Codex Mendoza (around 1541) is a mixed pictorial, alphabetic Spanish manuscript. The Florentine Codex, compiled 1545-1590 by Franciscan friar Bernardino de Sahagún includes a history of the Spanish conquest of the Aztec Empire from the Mexica viewpoint, with bilingual Nahuatl/Spanish alphabetic text and illustrations by native artists. The works of Dominican Diego Durán (before 1581), who drew on indigenous pictorials and living informants to create illustrated texts on history and religion. The colonial-era codices often contain Aztec pictograms or other pictorial elements.