Columbia subject headings:
Agriculture--Research.
Appropriate technology--Research--Developing countries.
Natural resources--Management--Research.
Organic farming--Research.
Sustainable agriculture--Research.
Harvard subject headings:
Cytology--Dictionaries.
Natural resources--Management--Research--International cooperation--Congresses.
Sustainable agriculture--Research--International cooperation--Congresses.
Princeton subject headings:
Natural resources--Management--Research--International cooperation--Congresses.
Sustainable agriculture--Research--International cooperation--Congresses.