The new thread (or another one) could also be a good place to document permissions to use non-public-domain work for the project to avoid future misunderstandings, wouldn’t it?
I got one last week from the Esperanto web magazine liberafolio.org by one of its founders Kalle Kniivilä. The magazine exists since 2003, I am importing the sentences in chunks with articles from one year each. They always contain around 800 sentences. So I expect that this can add around 10 000 new sentences in a high quality to the dataset. The site itself is licensed under CC BY 4.0 but it is okay for them if we publish unconnected sentences under CC0. I got the permission by mail and archived the mail. I always add the information that I got a permission when I import sentences from this source.
Should we have a different place to collect such permissions or do you agree that this fits well into the “copyright issues” thread? Or is it enough to just write it into the copyright field in the sentence-collector?