QUICKSILVER MESSENGER SERVICE/GRASS ROOTS/MAD RIVER 2nd printing 14×21 music 1968 MacLean! An Unfolded Music Poster (measures 14″ x 21 1/4″ [36 x 54 cm]). Quicksilver Messenger Service/Grass Roots/Mad River, the 1967 rock’n’ roll (rock and roll) music poster (“Bill Graham presents in San Francisco”; BG-87) promoting a concert featuring Quicksilver Messenger Service, Grass Roots and Mad River which took place at the Fillmore Auditorium in San Francisco, California from October 5th to the 7th. Note that this poster features wild art by Bonnie MacLean. Condition: very good to fine. The poster has never been folded and it is in excellent condition!