@Article{ MAZ_RICO:537-554,

author = { ALEXANDER MAZ MACHADO and LUIS RICO ROMERO } ,

title = { NEGATIVE NUMBERS IN THE 18TH AND 19TH CENTURIES:PHENOMENOLOGY AND REPRESENTATIONS },

journal = { ||ELECTRONIC JOURNAL OF RESEARCH IN EDUCATIONAL PSYCHOLOGY|| },

year = { 2009 },

issn = { 1696-2095 },

pages = { 537-554 },

}