1. Wess-Zumino-Witten model based on a nonsemisimple group
2. A class of string backgrounds as a semiclassical limit of WZW models
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4. Gauged WZW models and non-abelian duality, preprint THU-94/1, hep-th/9402031.
5. J.M. Figueroa-O'Farrill and S. Stanciu, Nonsemisimple Sugawara constructions, preprint QMW-PH-94-2, hep-th/9402035.