I watched recently a video by a YouTube channel called “Deka Glossai” which explained some books for learning Latin. He described one series called “In Usum Delphini” which, according to the Wikipedia page, was a series of texts used for the education of the son of King Louis XIV. It essentially, as the man on the video says, is a series of Latin text with Latin annotations, somewhat like Lingua Latina by Ørberg, but more complex. Does anyone know where these texts can be sought?
A good starting point:
Thank you
I put together this index of all the titles.