Columbia subject headings:
Agriculture--Colombia.
Developing countries--Colombia.
Harvard subject headings:
Soil surveys--Colombia.
Soil surveys--Llanos (Colombia and Venezuela)
Soils--Colombia.
Soils--Llanos (Colombia and Venezuela)
Princeton subject headings:
Soil surveys--Colombia.
Soil surveys--Llanos (Colombia and Venezuela).
Soils--Colombia.
Soils--Llanos (Colombia and Venezuela).