Okay, so it seems Amazon bought IVONA a while back and renamed it Polly (get it?) and the full list is here: https://docs.aws.amazon.com/polly/latest/dg/voicelist.html
― Something Super Stupid Cupid (James Redd and the Blecchs), Monday, 24 February 2020 03:31 (eleven months ago) link
Ah, Duolingo now using some Google Wavenet voices, like Eva and Luuk for Dutch. https://forum.duolingo.com/comment/41404647
― Indieland Phil and Indieland Don (James Redd and the Blecchs), Friday, 20 November 2020 02:20 (two months ago) link