In the UK, folk artists who were particularly significant included Marc Bolan, with his hippy duo Tyrannosaurus Rex, who used unusual instrumentation and tape effects, typified by the album "Unicorn" (1969), and Scottish performers such as Donovan, who combined influences of American artists like Bob Dylan with references to flower power, and the Incredible String Band, who from 1967 incorporated a range of influences into their acoustic based music, including medieval and eastern instruments. During the late 1960s and early 1970s, solo acts such as Syd Barrett and Nick Drake began to incorporate psychedelic influences into folk music with albums such as Barrett's The Madcap Laughs and Drake's Five Leaves Left.