Vu Ngoc Tru, Ha Thi Hang, Pham Duy Hoa, and Nguyen Viet Phuong, “LANDSLIDE SUSCEPTIBILITY MAPPING ALONG NATIONAL HIGHWAY-6, HOA BINH PROVINCE, VIETNAM USING FREQUENCY RATIO MODEL AND GIS”, INTERNATIONAL JOURNAL OF GEOMATE, vol. 21, no. 85, pp. 84–90, Sep. 2021.