Convention on Long-Range Transboundary Air Pollution, International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests, & European Union Scheme on the Protection of Forests Against Atmospheric Pollution. (1998). Forest condition in Europe: Results of the 1997 crown condition survey : 1998 technical report. United Nations Economic Commission for Europe, European Commission.
Παραπομπή σε μορφή Chicago (17η εκδ.)Convention on Long-Range Transboundary Air Pollution, International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests, και European Union Scheme on the Protection of Forests Against Atmospheric Pollution. Forest Condition in Europe: Results of the 1997 Crown Condition Survey : 1998 Technical Report. Brussels: United Nations Economic Commission for Europe, European Commission, 1998.
Παραπομπή σε μορφή MLA (9th εκδ.)Convention on Long-Range Transboundary Air Pollution, et al. Forest Condition in Europe: Results of the 1997 Crown Condition Survey : 1998 Technical Report. United Nations Economic Commission for Europe, European Commission, 1998.