Which entity is this text about?

Martha and the Vandellas (known from 1967 to 1972 as Martha Reeves and the Vandellas) were an American all-female vocal group formed in 1957. The group achieved fame in the 1960s with Motown. Selected Members of the group were inducted into the Rock and Roll Hall of Fame in 1995. Formed in 1957 by friends Annette Beard, Rosalind Ashford and Gloria Williams, the group eventually included Martha Reeves, who moved up in ranks as lead vocalist of the group after Williams' departure in 1962.

Teenagers Rosalind Ashford and Annette Beard first became acquainted after a local music manager hired them to be members of a girl group he named The Del-Phis. Ashford & Beard, along with then-lead vocalist Gloria Williams, performed at local clubs, private events, church benefits, YMCA events and school functions. They were also being coached by Maxine Powell at Detroit's Ferris Center. One of the group's first professional engagements was singing background for singer Mike Hanks.  The group originally had up to six members, shortened to four. After another member left the group, she was replaced by Alabama-born vocalist Martha Reeves, who had been a member of a rival group, the Fascinations and had also been a member of another group, the Sabre-Ettes. In 1960, the group signed their first recording contract with Checker Records, releasing the Reeves-led "I'll Let You Know". The record flopped. The group then recorded for Checkmate Records, a subsidiary of Chess Records, recording their first take of "There He Is (At My Door)". That record, featuring Williams on lead vocals, also flopped.  Briefly separated, Reeves returned to a solo career performing under the name Martha LaVaille, in hopes of getting a contract with emerging Detroit label Motown. After Motown staffer Mickey Stevenson noticed Reeves singing at a prominent Detroit club, he offered her his business card for an audition. Reeves showed up at Motown on a wrong date (Motown auditions were held at Thursdays, while Reeves showed up to Motown's Hitsville USA studios on a Tuesday). Stevenson, initially upset, told Reeves to look out for clients and other matters. Soon Reeves became Stevenson's secretary and later was responsible for helping acts audition for the label. By 1961, the group, now known as The Vels, were recording background vocals for Motown acts. Prior to her success as lead singer of The Elgins, Sandra Edwards (then going by her surname Maulett) recorded the song "Camel Walk", in 1962, which featured the Vels in background vocals. That year, the quartet began applying background vocals for emerging Motown star Marvin Gaye, singing on Gaye's first hit single, "Stubborn Kind of Fellow" After Mary Wells failed to make a scheduled recording session feigning a short illness, the Vels recorded what was initially a demo recording of "I'll Have to Let Him Go". Motown was so impressed by the group's vocals - and Martha's lead vocals in the song - that the label CEO Berry Gordy offered to give the group a contract. Figuring that being in show business was too rigorous, Williams opted out of the group. With Williams out, the remaining trio of Ashford, Beard and Reeves renamed themselves The Vandellas, after Detroit's Van Dyke Street and Reeves' favorite singer, Della Reese.
Martha and the Vandellas