https://9dok.net/document/zlg5on92-osterreichischezeitschriftf-urvermessungundgeoinformation-instituteofgeodesyandgeophysics-departmentofappliedandengineeringgeodesy-viennauniversityoftechnology-gusshausstr-michaelahaberler-afuzzysystemfortheassessmentoflandslidemonitoringdata.html