TY - JOUR A1 - Zhang, X. A1 - Yang, Y. A1 - Zhang, J. A1 - Liu, J. A1 - Wan, M. T1 - EXPLORATION AND PRACTICE OF BEIJING BELL AND DRUM TOWERS SAFETY DETECTION PROJECT JO - Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci. J1 - ISPRS-Archives VL - XLIII-B2-2020 SP - 1505 EP - 1511 Y1 - 2020/08/14 PB - Copernicus Publications SN - 2194-9034 UR - https://isprs-archives.copernicus.org/articles/XLIII-B2-2020/1505/2020/ L1 - https://isprs-archives.copernicus.org/articles/XLIII-B2-2020/1505/2020/isprs-archives-XLIII-B2-2020-1505-2020.pdf DO - 10.5194/isprs-archives-XLIII-B2-2020-1505-2020 ER -