The Funk Brothers were a group of Detroit-based session musicians who performed the backing to most Motown recordings from 1959 until the company moved to Los Angeles in 1972. Its members are considered among the most successful groups of studio musicians in music history. Among their hits are "My Girl", "I Heard It Through the Grapevine", "Baby Love", " I Was Made to Love Her", "Papa Was a Rollin' Stone", "The Tears of a Clown", "Ain't No Mountain High Enough", and "Heat Wave". Some combination of the members played on each of Motown's 100-plus U.S. R&B number one singles and 50-plus U.S. Pop number ones released from 1961 and 1972. There is no undisputed list of the members of the group. Some writers have claimed that virtually every musician who ever played on a Motown track was a "Funk Brother". There are 13 Funk Brothers identified in Paul Justman's 2002 documentary film Standing in the Shadows of Motown, based on Allan Slutsky's book of the same name. These 13 members were identified by both NARAS for the Grammy Lifetime Achievement Award and were recognized with a star on the Hollywood Walk of Fame. In 2007, the Funk Brothers were inducted into the Musicians Hall of Fame and Museum.