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Content of the book must follow: <isbn>_materie.pdf. Additional info can be added after materie with an additional _, and will be ignored. Examples:
9788203368578_materie.pdf
9788203368578_materie_booktitle.pdf
Cover of the book: <isbn>_omslag.pdf. Additional info can be added after omslag with and additional _, and will be ignored.
9788203368578_omslag.pdf
9788203368578_omslag_booktitle.pdf
Attachments to the book:
If only a single attachment exsits: <isbn>_vedlegg.pdf. Example:
9788203368578_vedlegg.pdf
If several attachments exists: <isbn>_attachment_<attachment-numbernumber>.pdf. Example:
9788203368578_vedlegg_1.pdf
9788203368578_vedlegg_2.pdf
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