404. That’s an error.

The requested URL /bookmarks/mark?op=edit&bkmk=https%3A%2F%2Fdata.bnf.fr%2Fen%2F11915031%2Fmichele_masson%2F&title=Mich%C3%A8le+Masson+%28adaptatrice+de+livres+pour+enfants%29 was not found on this server. That’s all we know.