Coetsiers, M.; Blaser, P.; Martens, K.; Walraevens, K. (2009). Natural background levels and threshold values for groundwater in fluvial Pleistocene and Tertiary marine aquifers in Flanders, Belgium. Environ. Geol. 57(5): 1155-1168. http://dx.doi.org/10.1007/s00254-008-1412-z, more
