A plurality of kinds of electronic source documents are held, and an electronic binder builder selects a desired electronic source document page from electronic source document pages of the plurality of kinds of held electronic source documents. Based on the selected electronic source document page, an integrated electronic document is composed, and page relation between pages in the electronic source document having electronic source document pages constituting the integrated electronic document and pages in a converted integrated electronic document of electronic source document pages constituting the converted integrated electronic document with the integrated electronic document converted into a predetermined file format is managed.