A Brief-ish History of METI. Part III: The Legacy of Frank Drake & Carl Sagan
Carl Sagan and Frank Drake were pivotal to the development of the Search for Extraterrestrial Intelligence (SETI) and Messaging Extraterrestrial Intelligence (METI), as exemplified by the Pioneer Plaques and Voyager Golden Records.
We haven't written up this one. Universe Today has the full story — the link below goes straight to it.