Hirt., C; Bürki, B.; Somieski, A.; Seeber, G. Modern Determination of vertical deflections using digital zenith cameras. Journal Surveying Engineering 136(1), Feb 2010, 1-12. doi:10.1061/(ASCE)SU.1943-5428.0000009.(PDF).
doi.org
Hirt., C; Bürki, B.; Somieski, A.; Seeber, G. Modern Determination of vertical deflections using digital zenith cameras. Journal Surveying Engineering 136(1), Feb 2010, 1-12. doi:10.1061/(ASCE)SU.1943-5428.0000009.(PDF).