http://www.erowid.org/li...ues_dekorne_complete.pdf^page 98, "smokable ayahuasca" all the way back in 1994, you will find what seems to me to be the first true "changa" mixture actually made(though they never called it changa) that was a leaf based smoking mixture that contains both extracted tryptamines and harmalas evaporated onto a leaf mixture.
Gracie and Zarkov were the first western people I know of to smoke harmalas followed by DMT, but this is the first instance I know of, where what we now call "changa" was made.
Long live the unwoke.