Tug of War (Paul McCartney album) and lasted from 3 February to 2 March, ending with "Ebony and Ivory" and "What's That You're Doing", two songs featuring Stevie Wonder. 10cc guitarist Eric Stewart also became a frequent collaborator of McCartney's during this period. Further sessions that summer were undertaken at Martin's AIR studios at Oxford Street, London. The sessions were so productive that several of its tracks were held over for McCartney's next album, "Pipes of Peace", which followed in 1983. The rest of 1981 was spent in a quiet fashion, with McCartney and Martin touching up the album and perfecting it. In a contemporary review
Paul McCartney and Wings all-star collection of musicians in London in aid of UNICEF and Kampuchean refugees. Also during this tour, a live version of the "McCartney II" track "Coming Up" was recorded in Glasgow and became Wings' sixth US number one hit the following year. Paul McCartney and his family arrived in Japan on 16 January 1980 for the planned eleven-date Wings' concert tour of Japan (due to visit Budokan Hall, Tokyo from 21 to 24 January 1980; Aichi-Ken, Taiiku-Kan, Nagoya on 25–26; Festival Hall, Osaka on 28; Osaka Furitsu-Kan, Osaka on 29; Budokan Hall, Tokyo from 31 January to 2 February 1980).