Lyric discussion by edp 

According to the book 1000 UK Number One Hits by Jon Kutner & Spencer Leigh Bjorn explained “Stig Anderson would come up with titles and I’d write a lyric round them. ‘Mamma Mia was one of them.” It was the last song to be written and recorded for their last album, Abba. In the studio was a marimba, an instrument of African origin, similar to the xylophone, but with wooden bars, which Benny began playing to see what it sounded like. He liked the sound it made and began using it with a tick-tock effect.

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