| Title | Authors | Year |
|---|---|---|
| Zeigerwerte von Pflanzen in Mitteleuropa |
Ellenberg,… |
1991 |
| Influence of HN3 and (HN4)2 SO4 on heathland vegetation |
Van der… |
1991 |
| Physiological-effects of long-term exposure to low concentrations of SO2 and NH3 on poplar leaves |
Hove, L.W.A… |
1991 |
| Forestry and soil protection in the UK |
Moffatt, A.… |
1991 |
| Mechansims of adaptions of plants to acid soils |
Marschner,… |
1991 |
| Increases in soil acidity in north west Wales between 1957 and 1990 |
… |
1991 |
| Decline of ectomycorrhizal fungi in Europe. |
Arnolds, E… |
1991 |
| Effects of sulphur dioxide on the development of fungal diseases of winter barley in an open-air fumigation system. |
Mansfield,… |
1991 |
| Single and Interactive Effects of Low Levels of O3, SO2 and NO2 on the Growth and Yield of Spring Rape. |
Adaros, G… |
1991 |
| Environmental Health Criteria 125 Platinum |
WHO, |
1991 |