Rahadi, I Ketut Satria, et al. “Intensity Of Rice Pest Pest Attack Using Keliling Observation Methods Linely Relationship With Outside Attacks of Arial Photograpy”. Jurnal BETA (Biosistem Dan Teknik Pertanian), vol. 7, no. 2, June 2019, pp. 1-7, doi:10.24843/JBETA.2019.v07.i18.