Markus Bärlocher, 07/09/2016 16:16:
I need the relation between ISO 639-3 and WP-shortcuts
I still have no idea what you mean by WP-shortcuts, but if you mean the MediaWiki/Wikimedia language codes then https://www.mediawiki.org/wiki/Language_code has all the pointers you need and https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes has most of the equivalencies between ISO 639-1 and ISO 639-3.
Nemo