Vertical Reference Systems: IAG Symposium Cartagena, Colombia, February 20–23, 2001 International Association of Geodesy Symposia, nr. 124 Editat de Hermann Drewes et al. 6 aug 2002 Hardback Preț: 1162.15 lei 1529.15 lei 38-44 zile -24%
Geodetic Reference Frames: IAG Symposium Munich, Germany, 9-14 October 2006 International Association of Geodesy Symposia, nr. 134 Editat de Hermann Drewes 30 iun 2009 Hardback Preț: 881.12 lei 1159.36 lei 38-44 zile -24%