Soil map of the world 1:5.000.000, volume III, Mexico and Central America / FAO Food and Agriculture Organization of the United Nations, UNESCO United Nations Educational Scientific and Cultural Organization

Mapa mundial de suelos 1:5.000.000, volume IV, América del Sur / FAO Food and Agriculture Organization of the United Nations, UNESCO United Nations Educational Scientific and Cultural Organization

Mapa mundial de suelos 1:5.000.000, volume IV, América del Sur / FAO Food and Agriculture Organization of the United Nations, UNESCO United Nations Educational Scientific and Cultural Organization