ABBA remain one of the world's most popular bands and their music got a new lease of life with the "Mamma Mia" stage show and film. The band's website said a deluxe edition of their final album, "The Visitors," would be released in April.

"For ABBA fans, the most sensational inclusion in the package will be the previously unreleased track, 'From A Twinkling Star To A Passing Angel (demos)'," a statement said.

"This is the first time since the 'Thank You For The Music' box set in 1994 that ABBA have opened the doors to the tape vaults to release previously unheard music from the group's heyday," it added.

The release will also feature bonus selections along with a DVD of rare and previously unreleased material from the archives.

The Visitors album was originally released in 1981.

ABBA, made up of Agnetha Faltskog, Anna-Frid Lyngstad, Benny Andersson and Bjorn Ulvaeus, racked up a string of hits in the 1970s and '80s, and their cult following has transformed them into some of Sweden's most recognizable figures.

(Reporting by Patrick Lannin, editing by Paul Casciato)

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