Task: Question Answering
Input (English): Passage: When Harrison joined the Quarrymen in 1958 his main guitar was a Höfner President Acoustic, which he soon traded for a Höfner Club 40 model. His first solid-body electric guitar was a Czech-built Jolana Futurama/Grazioso. The guitars he used on early recordings were mainly Gretsch models, played through a Vox amplifier, including a Gretsch Duo Jet that he bought secondhand in 1961, and posed with on the album cover for Cloud Nine. He also bought a Gretsch Tennessean and a Gretsch Country Gentleman, which he played on "She Loves You", and during the Beatles' 1964 appearance on The Ed Sullivan Show. In 1963 he bought a Rickenbacker 425 Fireglo, and in 1964 he acquired a Rickenbacker 360/12 guitar, which was the second of its kind to be manufactured. Harrison obtained his first Fender Stratocaster in 1965 and first used it during the recording of the Help! album that February; he also used it when recording Rubber Soul later that year, most notably on the song "Nowhere Man".In early 1966 Harrison and Lennon each purchased Epiphone Casinos, which they used on Revolver. Harrison also used a Gibson J-160E and a Gibson SG Standard while recording the album. He later painted his Stratocaster in a psychedelic design that included the word "Bebopalula" above the pickguard and the guitar's nickname, "Rocky", on the headstock. He played this guitar in the Magical Mystery Tour film and throughout his solo career. In July 1968, Clapton gave him a Gibson Les Paul, which Harrison nicknamed "Lucy". Around this time, he obtained a Gibson Jumbo J-200 acoustic guitar, which he subsequently gave to Dylan to use at the 1969 Isle of Wight Festival. In late 1968 Fender Musical Instruments Corporation gave Harrison a custom-made Fender Telecaster Rosewood prototype, made especially for him by Philip Kubicki. In August 2017, Fender released a "Limited Edition George Harrison Rosewood Telecaster" modelled after a Telecaster that Roger Rossmeisl originally created for Harrison. 
Question: What is the first name of the person who posed with a Gretsch Duo Jet guitar on the album cover for Cloud Nine?
Output (English): George.