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The third time's the charm for Annie Lennox.

The legendary Eurythmics singer got married last Saturday in London, her third marriage, People reports.

Lennox, 57, married Dr. Mitch Besser, 57, a Harvard-educated gynecologist who founded mothers2mothers, an organization based in Africa that aims to prevent mother-to-child transmission of HIV, keep mothers healthy, and empower women. Lennox, a committed activist known for raising awareness for HIV charities, met Besser through his charity which she fundraises.

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According to Mail Online, her two daughters, Lola, 22, and Tali, 19, served as her bridesmaids. Celebrity guests at the private ceremony, which reportedly took place on a boat on the Thames River, included Colin Firth and comedienne Ruby Wax.

Lennox confirmed the marriage with a tweet on Sunday of a photo of her wedding flowers with the simple caption, "Wedding flowers 15th September 2012."