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pdf English: RODRÍGUEZ POSADA, Emilio José; GONZÁLEZ BERDASCO, Ángel; SIERRA CANDUELA, Jorge A.; NAVARRO SANZ, Santiago; SAORÍN, Tomás (2012)...
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archive.org/web/20161023151624/http://www.panoramio.com/user/6707551?with_photo_id=67093111 operator: Panoramio described at URL: https://web.archive...