A holding stand is constituted by a carrying case for holding sheets of electronic paper and a base for uprightly supporting the carrying case that is substantially vertical. From the holding stand, two page fields, each expressing the number of pages of sheets of electronic paper to be displayed and position page field expressing a current page position of electronic paper and incremented on each of the sheets, are added to image data, and the image data is output to the sheets of electronic paper. In each sheets, when the two page fields coincide with each other in comparison between the two page fields, an image based on the image data is displayed in a display region. When the two page fields are different from each other, the position page field is incremented by one, and the position page field is transmitted to the next electronic paper.