Disease incidence of freshwater fish in the Special Region of Yogyakarta, Indonesia Yuli Purwandari Kristianingrum, Bambang Sutrisno, Sitarina Widyarini and Kurniasih Sugiyono BIO Web Conf., 33 (2021) 06001 Published online: 23 August 2021 DOI: 10.1051/bioconf/20213306001