الموضوعات المستخلصة من بحثك.
الموضوعات المستخلصة من بحثك.
Contingent valuation
AIDS (Disease)
1
Costs
1
Counseling of
1
Econometric models
1
Economic aspects
1
Environmental economics
1
HIV infections
1
HIV-positive persons
1
Methodology
1
National parks and reserves
1
Outdoor recreation
1
Patients
1
Pollution
1
Prevention
1
Public goods
1
Purification
1
Recreation areas
1
Services for
1
User charges
1
Valuation
1
Water
1
Water quality
1
-
1
-
2
-
3