Columbia subject headings:
Fertilizers--Prices--Developing countries--Case studies--Congresses.
Fertilizers--Prices--Developing countries--Congresses.
Harvard subject headings:
Fertilizers--Developing countries--Price policy--Case studies.
Fertilizers--Developing countries--Price policy.
Princeton subject headings:
Fertilizers--Developing countries--Prices--Case studies--Congresses.
Fertilizers--Developing countries--Prices--Congresses.