The Dick Cavett Show
From Muppet Wiki
The Country Trio appeared on The Dick Cavett Show in 1973, singing "Mama Don't Allow."
Jim Henson, Frank Oz, Jerry Nelson and Caroll Spinney also made an appearance in 1971 promoting The Muppet Alphabet Album and The Frog Prince. The Muppets on the show (some seen with their performers, some not) included Kermit the Frog, Lothar, Cookie Monster, Thog, and Anything Muppets.
