The Marvelettes

The Marvelettes were an all-girl group who achieved popularity in the early to mid-1960s. They consisted of schoolmates Gladys Horton, Katherine Anderson (later Katherine Anderson Schnaffer), Georgeanna Tillman (later Georgeanna Tillman-Gordon), Juanita Cowart (later Juanita Cowart Motley) and Georgia Dobbins, who was replaced by Wanda Young (later Wanda Rogers) prior to the group signing their first deal. The group was the first major successful act of Motown Records after The Miracles and were its first significant successful girl group on the label's early years after the release of the number-one single, "Please Mr. Postman", one of the first number-one singles recorded by an all-female vocal group and the first by a Motown recording act.

source: Wikipedia