Temporal Gravity Variations near Shrinking Vatnajökull Ice Cap, Iceland - Jacoby, Wolfgang R.; Hartmann, Oliver; Wallner, Herbert; Smilde, Peter L.; Bürger, Stefan; Sjöberg, Lars E.; Erlingsson, Sigurdur; Wolf, Detlef; Klemann, Volker; Sasgen, Ingo (Birkhäuser Basel, 2009)