TY - JOUR T1 - Digital Surface Models for GNSS Mission Planning in Critical Environments JF - Journal of Surveying Engineering Y1 - 2013 A1 - Ackermann, S. A1 - Angrisano, A. A1 - Del Pizzo, S. A1 - Gaglione, S. A1 - Gioia, C. A1 - Troisi, S. UR - http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29SU.1943-5428.0000119 ER -