@inbook{ GUTIERREZ_Rico-Romero_CASTRO_Castro-Martinez:179-205,
author = { JOSE GUTIERREZ PEREZ and Luis Rico-Romero and ENRIQUE CASTRO MARTINEZ and Encarnacion Castro-Martinez } ,
title = { ON THE CLASSIFICATION OF TWO-STEPS ADDITIVE PROBLEMS },
booktitle = { DIDACTICS OF MATHEMATICS-TECHNOLOGY IN EDUCATION },
isbn = { 960-312-063-4 },
publisher = { ART OF TEXT },
pages = { 179 - 205 },
year = { 1997 },
}