Management, regulation and environmental impacts of nitrogen fertilization in northwestern Europe under the Nitrates Directive: a benchmark study

H.J.M. van Grinsven, H.F.M. ten Berge, Tommy Dalgaard, B. Fraters, P. Durand, A. Hart, G. Hofman, Brian H. Jacobsen, S.T.J. Lalor, J.P. Lesschen, B. Osterburg, K.G. Richards, A.-K. Techen, F. Vertès, J. Webb, W.J. Willems