Nearly every paper here is licensed CC BY 4.0 or dedicated CC0. A paper whose licence cannot be resolved is treated as rejected and is not generated.

There is one other basis, and it is rare. A paper may also appear here when an author has given permission directly and a person has recorded who gave it and when. At the time of writing that applies to one paper in the library. Those pages say so in place of a licence, because permission to appear here is not an open licence and does not grant you any reuse rights.

What you may do with a walkthrough therefore depends on the paper it is built from. Where the source is CC BY, you may reuse and redistribute the walkthrough and the deck — including commercially — if you give appropriate credit, link the licence, and indicate what was changed. Each page carries all three. Where the source is CC0, there are no conditions. Where a paper is here on permission alone, treat it as all rights reserved and ask the authors.

Every page credits the authors, links the source, names the basis, and states that the walkthrough is an adaptation they have not endorsed.

Takedowns. We remove things when asked. CC BY permission is irrevocable while its terms are met, so for an openly licensed paper a removal is something we choose to do rather than something the licence compels — but that reasoning does not cover every complaint, and we do not treat it as a reason to refuse one. Other rights, other licences and permission-based material all work differently. Ask, and we will take it down. See takedown.