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"L'anisotropie de l'espace. La nécessaire révision de certains postulats des théories contemporaines. Les données de l'expérience" by Maurice Allais, Clément Juglar, Paris, (p. 640), 1997.
"Joseph Gordon-Levitt Talks HITRECORD ON TV, How the Idea Came about, His Collaborative Company, Inspiring People to Contribute, and Plans for Season 2". Interview with Christina Radish, collider.com. January 15, 2014.