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\bibitem{Graf_etal2011} Graf, S., Kinshuk, Chen, N. S., Chang, M., Dron, J., Wen, D., et al. (2011). Adaptabilidad y Personalizacion de Ambientes de Aprendizaje Ubicuos -- Un enfoque basado en estilos de aprendizaje (in Spanish; English title: Adaptivity and Personalization in Ubiquitous Learning Environments -- Learning Styles based Approach). \textit{Revista Magisterio}, \textit{52}(5), 30--39.

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