In
https://github.com/remixlabs/docs-public/wiki/mix-syntax
some Links are wrong.
For those wrong links it looks as if the documents don't exist (create. new page).
But when the links are corrected, the documents are available.
Example:
wrong: https://github.com/remixlabs/docs-public/wiki/directives
correct: https://github.com/remixlabs/docs-public/wiki/mix-directives