[Canadaoer] Ebook Best Practice

Hello Canada OER List I have a couple questions I'm hoping I can find answers for on this list. We're in the process of developing a series OERs related to digital accessibility, to be distributed in various forms including HTML, epub, pdf, etc. We're experimenting with Pressbooks as the platform for assembling the content, content that was previously part of a MOOC based course. The content is quite varied, with typical text and images, lot's of video, and a variety of interactive activities, most of which link out to resource websites specifically created for the courses. 1. What is the best practice for including external video, with epub books in particular? From what I read, it seems the video needs to be included in the files for an epub book. This is not an option for us, given there are 30 or 40 videos in the course, which if added directly to the epub, would make the book's size too large to be usable for many (Gigabytes in size).  Linking from Youtube etc. does not seem to work for epubs and PDFs. We've ended up using the YouTube embed code, to embed the videos for those viewing the book online, but for epubs and PDFs the videos are blank spaces. We've included links to the videos as a backup, so readers can go to YouTube and view the videos there. Question: Is there a better way to include external videos in epubs (and PDFs)? 2. Pressbooks allows iframes, into which we can open external activities from within the web version of the book, but again when exported as an epub or PDF, they show up as a blank space. Similar question: Question: Is there a best practice for linking external content into epubs and PDFs? Thanks greg P. S. is there an archive of this list one can go back and review? -- Greg Gay IT Accessibility Specialist Digital Education Strategies The G. Raymond Chang School of Continuing Education Ryerson University Tel: 416 979-5000 #2061