Aie, Pourquoi On S'Aime, Angela & Roberto duet

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O la la!!! Where did this come from? Unexpected but most welcomed. When I listened to the sample on fnac.com I had some doubts. They only give you 30 seconds. A few days ago I talked about how different an opera singer sounds when the voice is used for another type of music. I guess you finished listening by now. Well, it's Angela's voice indeed :)
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This song is on Roberto's latest CD released yesterday, Hommage a Luis Mariano. If anybody knows, let me know please when it was recorded (from the booklet or other sources...). EDIT: the CD was first released in 2006. My question refers to this song in particular.
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The CD is on sale also as MP3 files. The song is also on Roberto's previous "Hommage CD", but there's another lady singing there.
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