Add reference to the Endorsed Note about a UDF catalog #16
Description
Jon Juaristi Campillo and Markus Demleitner have published an Endorsed Note (currently in PR) describing an IVOA consensus on some User Defined Functions:
Endorsed Note "Catalogue of ADQL User Defined Functions " - PR-1.0, Jon Juaristi Campillo, et.al.
There is no obligation to implement them. They are just recommandations for function names (all prefixed with ivo_) and signatures.