Map background: Natural Earth (public domain)
Language point data: Glottolog (licence: Creative Commons — Attribution-ShareAlike 3.0 Unported — CC BY-SA 3.0)
Map markers: font: Overpass (licence: SIL OFL/LGPL), character: 💬 — U+1F4AC SPEECH BALLOON.
Label font: U001Con Italic (foundry: URW++, licence: AFPL)