Alphonse Pinart was never a book dealer. There is not much internet information on Alphonse Pinart, but the biography composed by Ross Parmenter documents that Alphonse Pinart was an ethnolinguist and protégé of Charles Étienne Brasseur de Bourbourg whom he met at the 1867 World Fair in Paris. Brasseur bequeathed his library to Pinart though Pinart was far more interested in other aspects of the Americas and sold Brasseur’s collection in 1883 which is how Edward E. Ayer obtained it.
Parmenter, Ross. Explorer, Linguist and Ethnologist: A Descriptive Bibliography of the Published Works of Alphonse Louis Pinart, With Notes on his Life. Los Angeles: Southwest Museum, 1966.
Woodruff, John M. The “most futile and vain” Work of Father Francisco Ximénez: Rethinking the Context of Popol Vuh. U. Alabama, 2009. Print.