4Kraus K, Pfeifer N. Determination of Terrain Models in Wooded Areas with Airborne Laser Scanner Data[ J]. ISPRS Journal of Photogrammetry and Remote Sensing, 1998,53 (4) :193 ~203.
5Vosselman G. Slope based filtering of laser altimetry data [ A]. In:International Archives of Photogrammetry and Re- mote sensing, vol. XXXIII, Part B3, Amsterdam, 2000 : 935 -942.
7Axelesson P. DEM from laser scanner data using adaptive TIN models [J]. International Archives of Photogrammetry and Remote Sensing, 2000,33(B4/1):110-117.
8Vosselman G. Slope based filtering of laser altimetry data [J]. International Archives of Photogrammetry and Remote Sensing, 2000, 33(B3/2; PART 3): 935-942.
9Roggero M. Airborne laser scanning-clustering in raw data [J]. International Archives of Photogratmnetry Remote Sensing and Spatial Information Sciences, 2001, 34(3): 227-232.