Netherlands hydrogeological research in international cooperation : proceedings of the national meeting in Delft, The Netherlands, 31 March 1994 / ed. J.C. Hooghart, E. RomijnEvaluation and protection of groundwater resources "From vision to action", conference Wageningen, 20 September 2000Management of aquifer recharge and subsurface storage : making better use of our largest reservoir / [ed.: Albert Tuinhof, Jan Piet Heederik]Arsenic in groundwater : a world problem : proceedings seminar Utrecht 29 November 2006 / ed. Tony Appelo