While i appreciate your time to write and share your idea, this is an example of overcomplicate things. Your idea require some technical knowledge and require specific set of action which could be forgitten easily.

Quote from: jordapoulton on October 02, 2022, 07:59:22 PM

--> Perhaps, but it seems to me that the chances of Github being shutdown are pretty low... Probably lower than my piece of paper being stolen/lost/burnt in a fire, but perhaps not.

GitHub is popular, so i agree it's unlikely GitHub will be shutdown in the future. But there's no guarantee,
1. It'll remain free
2. Letting free user upload lots of code with little limitation.
3. Keep code from inactive user.

For reference, GitLab already make some limitation to free user few months ago.

Quote from: PawGo on Today at 06:15:20 AM

Quote from: PrimeNumber7 on October 02, 2022, 10:25:44 PM

You can mitigate your chances of losing access to the particular version of the book by choosing a book that will likely continue being published, like the bible.

You beed much more information than just a title/author. You need publisher, year of publication, release number etc. For book written in different language you need translator name. That’s why ISBN is used, the same book may be published in different formats, font size etc - any change breaks your triplet constraint.

And if the main reference is e-book, you also need to pay attention of the e-book format. For example, epub file format have dynamic layout where total page depending on font size and screen resolution.