@Article{ Ruiz-Ledesma_LUPIÁÑEZ:397-424,

author = { Elena Fabiola Ruiz-Ledesma and JOSÉ LUIS LUPIÁÑEZ GÓMEZ } ,

title = { DETECTING PSYCHOLOGICAL OBSTACLES TO TEACHING AND LEARNING THE TOPICS OF RATIO AND PROPORTION IN SIXTH GRADE PRIMARY PUPILS },

journal = { Revista Electrónica de Investigación Psicoeducativa y Psicopedagógica },

year = { 2009 },

volume = { 17 },

pages = { 397-424 },

doi = { http://www.investigacion-psicopedagogica.org/revista/new/english/index.php?n=17 },

}