The Lincoln tape is stated here
http://tela.sugarmegs.org/_asxtela/asxcards/SandyDennyAndTheHappyBlunderers1971-07-24LincolnFolkFestival.html
as being recorded by Nick Ralph who worked for the U.S. magazine Dark Star. Does this tally with your info? In that case we owe him a huge debt of gratitude!