GPLv3|L8R --what years to put in the copyright notice?

Hi, When converting to GPLv3 or later we have found some files that does not have a copyright notice but that have a good documentation of the authors to the file. A copyright notice should then be added documenting that fact. Right!? But how much effort should be put in finding what years the respective author did his work? The version info of the files does not reveal all, if anything sometimes. Suggestions on how to solve this are appreciated. Yours -- %% Mats _______________________________________________ XEmacs-Beta mailing list XEmacs-Beta(a)xemacs.org http://lists.xemacs.org/mailman/listinfo/xemacs-beta