Convention on Long-Range Transboundary Air Pollution & International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests. (1993). Forest condition in Europe: Results of the 1992 survey: 1993 report. United Nations Economic Commission for Europe, Commission of the European Communities.
Παραπομπή σε μορφή Chicago (17η εκδ.)Convention on Long-Range Transboundary Air Pollution και International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests. Forest Condition in Europe: Results of the 1992 Survey: 1993 Report. Brussels; Geneva: United Nations Economic Commission for Europe, Commission of the European Communities, 1993.
Παραπομπή σε μορφή MLA (9th εκδ.)Convention on Long-Range Transboundary Air Pollution και International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests. Forest Condition in Europe: Results of the 1992 Survey: 1993 Report. United Nations Economic Commission for Europe, Commission of the European Communities, 1993.