This is a Markdown conversion of the scanned PDF of "Italiano Secondo il Metodo Natura" published in 1962 by the Nature Method Centre accessible here.
The first two chapters have also been recorded and uploaded to Youtube by the user Polymathy. Playlist is viewable here.
I am learning Italian via this method and transcribing as I go along with plans to eventually produce an EPUB through Pandoc, which will include all illustrations and sidenotes from the book.