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If you are using Quark Xpress, please follow these alternate instructions.
To load a preset into InDesign:
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Open the InDesign file representing the book's interior.
Select the InDesign menu item: File > Adobe PDF presets > ebook-interior…
Follow the ebook naming conventions in the "Save As" field of the "Export" window when saving the file. Specifically, the cover should be named ISBN_ebook_cvr.pdf and the interior should be named ISBN_ebook_int.pdf.
Export all pages.
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