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As we acquire and catalog born-digital material, it should be noted that there will be a description of the digital storage requirement of the material, but there may not be a physical container taking up shelf space [e.g., acquisition of a website]. In these cases, the field will be formatted with a term from AAT describing the documents (not the file or encoding format) and an expression of the storage requirement in MB as follows:
300 $$3 Web pages (document genres): $$a (2.8 MB)
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