1589 20160222141731.0 10.1029/2006EO300005 DOI SISMOimport-104 Van Camp, Michel 2006 Karst aquifer investigation using absolute gravity Meeus R, Philippe Quinif, Yves Kaufmann, Olivier Van Ruymbeke, Michel Vandiepenbeeck, Marc Camelbeeck, Thierry EOS, Transactions AGU 87(n°30) 2006 298 published in REFERD