An ω-power of a finite context-free language which is Borel above ∆0ω
Duparc J., Finkel O., 2007., Foundations of the Formal Sciences V. Infinite Games pp. 109-122 dans Bold S. , Löwe B., Räsch T. , van Benthem J. (eds.) Infinite Games, Papers of the conference Foundations of the Formal Sciences V, held in Bonn, November 26-29, 2004, Studies in Logic. Peer-reviewed, College Publications, London.
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