According to Lennon in 1970, "Norwegian Wood" was his creation, with McCartney assisting on the middle eight. In 1980, Lennon changed his claim, saying it was "my song completely". Since Lennon's death, however, McCartney has contended that Lennon brought the opening couplet to one of their joint songwriting sessions, and that they finished the song together, with the middle eight and the title (and the "fire") being among McCartney's contributions. McCartney's statement about the level of his involvement was one of the controversial claims he made in his 1997 authorised biography, "Many Years from Now". Regardless, Lennon began writing the song in January 1965, while on holiday with his wife, Cynthia, and record producer George Martin at St. Moritz in the Swiss Alps. Over the following days, Lennon expanded on an acoustic arrangement of the song, which was written in a Dylanesque time signature, and showed it to Martin while he recovered from a skiing injury. In his book "The Songs of Lennon: The Beatle Years", author John Stevens describes "Norwegian Wood" as a turning point in folk-style ballads, writing that "Lennon moves quickly from one lyrical image to another, leaving it up to the listener's imagination to complete the picture". He also said the song marked a pivotal moment in Lennon's use of surreal lyrics, following on from the songs "Ask Me Why" and "There's a Place".