@article {1463, title = { Distribution and decline of endangered herbaceous heathland species in relation to the chemical composition of the soil}, journal = {Plant and Soil}, volume = {148}, year = {1993}, pages = {137-143}, author = {Houdijk, A.L.F.M. and Verbank, P.J.M. and van Dijk, H.F.G. and Roelofs, J.G.M.} }