Nugroho, Ardiyanto W, et al. “Efforts to Improve Ecotourism Management for Bekantan Conservation from visitors’ Perspectives: A Case Study in Balikpapan East Kalimantan”. Jurnal Penelitian Kehutanan Wallacea, vol. 8, no. 1, Mar. 2019, pp. 57-69, doi:10.18330/jwallacea.2019.vol8iss1pp57-69.