Example: https://www.softwareheritage.org/check-deposit-2020-11-15T21:58:29.744061
Je-suis-gpl is also found here
https://archive.softwareheritage.org/swh:1:rev:e76ea49c9ffbb7f73611087ba6e999b19e5d71eb;origin=https://forge.softwareheritage.org/source/jesuisgpl/;visit=swh:1:snp:68c0d26104d47e278dd6be07ed61fafb561d0d20/
Choose a coherent url and do checks to this url.