STOCKHOLM, Sweden (CNN) -- Bjorn Ulvaeus was one half of the songwriting genius behind Swedish pop legend ABBA. After the band split up in 1982 Ulvaeus turned his talents to writing musicals, including "Mamma Mia," now a blockbuster movie. Bjorn Ulvaeus on the ABBA phenomenon: "I'm amazed how this could happen. I'm just grateful and humble." He took My City_My Life on a tour of his home town of Stockholm and talked about his past and future as pop royalty. CNN: What is the secret of ABBA's success? Bjorn Ulvaeus: I think the secret behind the fact that our songs are still around and that ABBA became so big is a lot of factors together. But one of them was definitely that we put so much effort into song writing.
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Bjorn Ulvaeus is half of the songwriting pair behind Swedish pop legend ABBA
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He lives in Stockholm, which he describes as being "dynamic" and trendy
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Ulvaeus thought ABBA would be forgotten and is "amazed" by its popularity
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An ABBA museum is being planned for Stockholm
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