i am using several OSS libs from github in my project and want to add them to a combined licence file (using the amazon oss attribution builder) so i can attribute their work.
However, several of them them contain only a license file without a copyright notice with contributor(s) and years.
-> There is no "Copyright 2012-2017 MSteiger and Contributors" or similar like in other projects.
Is there some kind of best practice for adding this kind of missing information? Or should i just leave year and contributor information empty?