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I'm also a fan of this singer and particulary this song but you have to know that it will be very difficult or even impossible to contact her because it's a song from 1981 and the company who owned the copyrights when the 12" was released it's now defunct(*), I didn't find any company who owns the back catalog. I also looked for the singer on the web but didn't find her contact data on social network or elsewhere.
What to do in this case in order to publish it on Spotify ? Could it be that it will be never available ?