[4] Universal Container Format - Adobe Acrobat Navigator - Adobe Learning Resources, , https://web.archive.org/web/20110625081756/http://learn.adobe.com/wiki/display/PDFNAV/Universal+Container+Format
[1] null, , https://developer.adobe.com/creative-cloud-libraries/docs/integrate/references/glossary/#universal-container-format-ucf
Universal Container Format (UCF)
A general-purpose container technology that collects a related set of files into a single-file container. UCF is based on the widely used ZIP archival format, and conforms to the OEBPS Container Format guidelines, as well as the Open Document Format 1.0 specification. Off-the-shelf ZIP tools can be used to open, inspect, and extract files from UCF packages.
[3] GitHub - hainesr/ruby-ucf: A Ruby library for working with UCF documents., https://github.com/hainesr/ruby-ucf