[jaustin]

I wish I knew the paper, but https://github.com/chirp was a proprietary data-over-sound-through-air implementation that worked pretty well and sounded really cute (to my ears, anyway). It's not a paper, but there's this https://www.scientia.global/wp-content/uploads/2017/10/Chirp...

[freeamz]

There are a lot open source one:

https://github.com/quiet/quiet-js

Remember seeing them quite a bit a few years ago.