DOLORES FLORES, C.; ALARCÓN BELLO , G.; ALBARRÁN MILLÁN, D. F. ALTERNATIVE CONCEPTIONS ABOUT CARTESIAN GRAPHS OF MOTION: THE CASE OF VELOCITY AND TRAJECTORY. Revista Latinoamericana de Investigación en Matemática Educativa, v. 5, n. 3, p. 225–250, 30 Nov.2002.