Convention on Long-Range Transboundary Air Pollution & International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests. (1994). Forest condition in Europe: Results of the 1993 survey : 1994 report. United Nations Economic Commission for Europe, European Commission.
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 1993 Survey : 1994 Report. Brussels; Geneva: United Nations Economic Commission for Europe, European Commission, 1994.
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 1993 Survey : 1994 Report. United Nations Economic Commission for Europe, European Commission, 1994.