Wieringa, K. (1995). Environment in the European Union, 1995: Report for the review of the Fifth Environmental Action Programme :the update to the 1992 report on the state of the environment in the European Union requested by the European Commission. Luxembourg: Office for Official Publications of the European Communities.

Wieringa, Keimpe. Environment in the European Union, 1995: Report for the Review of the Fifth Environmental Action Programme :the Update to the 1992 Report On the State of the Environment in the European Union Requested By the European Commission. Luxembourg: Office for Official Publications of the European Communities, 1995.

Wieringa, Keimpe. Environment in the European Union, 1995: Report for the Review of the Fifth Environmental Action Programme :the Update to the 1992 Report On the State of the Environment in the European Union Requested By the European Commission. Luxembourg: Office for Official Publications of the European Communities, 1995.