Perhaps you can cite this paper:
As of September 2013.. . Five less frequently traded currencies have been discontinued (NZD, DKK, SEK, AUD, CAD).. The total number of currency-maturity fixing pairs has been
reduced from 150 to 35..
see also "Exhibit A" on page 2.
The 7 pre-EUR currencies that had LIBOR published were Deutsche mark (DEM), ...