the question of valeriano's authorship of the nahuatl text known as "nican mopohua" has become a point of contention in the long-running dispute over the historicity of the apparitions of the virgin mary (under the title our lady of guadalupe) to juan diego in 1531. the "nican mopohua" was published in 1649 by luis lasso de la vega as part of a composite text known from its opening words as the "huei tlamahuiçoltica", and de la vega's claims of authorship in the preface to that work notwithstanding, the "nican mopohua" has long been attributed to valeriano. this attribution is based on a tradition dating back to the informaciones jurídicas de 1666 and the assertions of luis becerra tanco and, subsequently, don carlos de sigüenza y góngora as to valeriano's authorship and as to their acquaintance with the relative manuscripts in his hand-writing.