https://learn.microsoft.com/en-us/openspecs/office_file_formats/ms-offfflp/8aea05e3-8c1e-4a9a-9614-31f71e679456?redirectedfrom=MSDN
[MS-OFFFFLP]: Office File Formats | Microsoft Learn
This documentation contains detailed technical specifications for file formats implemented in certain Office applications,
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