Performance analysis of freeware filtering algorithms for determining ground surface from airborne laser scanning dataJulge, Kalev; Ellmann, Artu; Gruno, AntiJournal of applied remote sensing2014 / p. 083573-1-083573-15 : ill https://doi.org/10.1117/1.JRS.8.083573 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS