Teen Angel by Donovan (covered by Dean & Britta)
And Donovan turns up for his third appearance in "Originals" - Teen Angel was the b-side of his classic 45 Hurdy Gurdy Man in 1968.
Dean & Britta's cover was released on their second album, Back Numbers, in 2007
And that's pretty much all I know.
See all the posts in the "Originals" series