Sandy Denny, born Alexandra Elene Maclean Denny (6 January 1947 – 21 April 1978), was an English singerand songwriter who has been described by Allmusic's Richie Unterberger as "the pre-eminent British folk rocksinger". She emerged in the mid 1960s while still a teenager, performing on the folk revival scene where she displayed her mastery of traditional singing and interpretation. Her song, "Who Knows Where the Time Goes?", written during these early years, has been covered by numerous artists and is regarded as a classic of its type.
Over a ten year career Sandy Denny left an extensive legacy and remains influential. She is remembered for the crystal-clear purity but also the strength of her voice as well as her pivotal involvement with the British folk rock movement, where as a member of Fairport Convention, she moved the band away from west coast American cover versions and into performing traditional material and original compositions. She is also noted for her duet with Robert Plant on Led Zeppelin's fourth album in 1971, on the song "The Battle of Evermore", and to date she remains the only guest vocalist on a Led Zeppelin album. (...)
Denny's renown grew after her death, and her songs have been covered by many other artists. She is considered a founder of the British folk rock movement and perhaps its most important female singer and personality. It has been suggested that her effortless and smooth vocal delivery still sets the standard for many of today's female folk-based singers.[ http://en.wikipedia.org/wiki/Sandy_Denny