content reference

If you want to include this page: https://github.com/ethereum/wiki/wiki/White-Paper in your gitbook you have to have this: {% include "git+https://github.com/ethereum/wiki.wiki.git/White-Paper.md" %} How you compose the link? you go to the repo page, in this case: https://github.com/ethereum/wiki and copy the git clone url - it's on the right side: https://github.com/ethereum/wiki.git Because our page is in the wiki section of the repo, we get the git clone url of the wiki by inserting ".wiki" like this: https://github.com/ethereum/wiki.wiki.git Then, just add the title of the page and the ".md" extension. https://github.com/ethereum/wiki.wiki.git/White-Paper.md

just 1 more example: {% include "git+https://github.com/ethereum/cpp-ethereum.wiki.git/Solidity-Features.md" %}

Also, make sure you are on 2.x.x version of gitbook builder.