I do not seek to open a debate over which reference system is better, but for tokens from the area of Yugoslavia, probably the best reference catalogue for tokens is Mandic (these days). There might come a day, when someone issues a better/wider/richer catalogue.
But for now to manually copy some TC references to second base and Mandic reference to first base, is truly low quality manual work. This is solely my point here, other users can have other wishes...
I propose a button next to each reference field, where referees can easily move reference numbers up or down the ladder (or maybe even better - lets robot move/change the reference numbers to first position).
This idea probably does open at least a question which reference should be number one with certain states or coins/token types (not all), since the first reference number is currently the only value on which you can sort your collection:

I hope (I have written over this before) that Xavier would be willing to pull thur another upgrade where in case user selects "Reference" option to list coins/tokens in collection, she/he can also select the reference numbering system to list its coins/tokens.
LP