Columbia subject headings:
Environmental policy--Sweden--Gotland--Mathematical models.
Gotland (Sweden)--Economic conditions.
Natural resources--Sweden--Gotland--Mathematical models.
Power resources--Sweden--Gotland--Mathematical models.
Harvard subject headings:
Ecology--Mathematical models
Environmental policy--Sweden--Gotland--Mathematical models.
Gotland (Sweden)--Economic conditions--Mathematical models.
Gotland (Sweden)--Economic conditions.
Natural resources--Sweden--Gotland--Mathematical models.
Natural resources--Sweden--Gotland.
Power resources--Sweden--Gotland--Mathematical models.
Power resources--Sweden--Gotland.
Princeton subject headings:
Ecology--Mathematical models.
Gotland (Sweden)--Economic conditions.
Natural resources--Sweden--Gotland.
Power resources--Sweden--Gotland.