16. A system comprising: one or more processors; one or more computer-readable media containing instructions that are executable by the one or more processors to perform actions comprising: obtaining page text and corresponding page labels from individual pages of a print version of a book; determining a page-to-label mapping between the individual pages and the page labels obtained from the print version; comparing the page text of the individual pages to an electronic version of the book to determine the positions of the individual pages within the electronic version; creating, based at least in part on the comparing and the page-to-label mapping, a page/position map as a data object separate from content of the electronic version, wherein the page/position map indicates correspondences between the page labels obtained from the print version and positions within the electronic version; and paginating the electronic version in accordance with the comparing.
16. A system comprising: one or more processors; one or more computer-readable media containing instructions that are executable by the one or more processors to perform actions comprising: obtaining page text and corresponding page labels from individual pages of a print version of a book; determining a page-to-label mapping between the individual pages and the page labels obtained from the print version; comparing the page text of the individual pages to an electronic version of the book to determine the positions of the individual pages within the electronic version; creating, based at least in part on the comparing and the page-to-label mapping, a page/position map as a data object separate from content of the electronic version, wherein the page/position map indicates correspondences between the page labels obtained from the print version and positions within the electronic version; and paginating the electronic version in accordance with the comparing. 19. The system of claim 16 , wherein the obtaining comprises machine-based optical character recognition.