| Title | Authors | Year | 
|---|---|---|
| Acid Rain - Critical and Target Load Maps for the United Kingdom | 
                               Environment…  | 
                                                                                        1991 | 
| Environmental Health Criteria 125 Platinum | 
                               WHO,  | 
                                                                                        1991 | 
| Zeigerwerte von Pflanzen in Mitteleuropa | 
                               Ellenberg,…  | 
                                                                                        1991 | 
| Proceedings of the 2nd workshop on sources of variation in ecotoxicological tests with Daphnia magna | 
                               Van der…  | 
                                                                                        1991 | 
| Effects of ionising radiation on aquatic organisms | 
                               National…  | 
                                                                                        1991 | 
| Nitrogen Uptake and Allocation by Calluna-Vulgaris (L) Hull and Deschampsia-Flexuosa (L) Trin Exposed to 15NH3 | 
                               Dueck, T.A…  | 
                                                                                        1991 | 
| The yield of winter cereals exposed to sulphur dioxide under field conditions. | 
                               McLeod, A.R…  | 
                                                                                        1991 | 
| Critical Load Maps for the United Kingdom I: Soil | 
                               UKCLAG,  | 
                                                                                        1991 | 
| Effects of nitrogen loading on wetland ecosystems, with particular reference to atmospheric deposition | 
                               Morris, J.T…  | 
                                                                                        1991 | 
| Air pollution and agriculture | 
                               Ashmore, M.…  | 
                                                                                        1991 |