(1997) Retroviruses (freely searchable online book) ICTV: International Committee on Taxonomy of Viruses - searchable virus taxonomy, updated versions in 2007 and 2008.
바이로이드 부수체 프리온 바이러스 분류 바이러스의 진화 바이러스병 (영어) ICTV: International Committee on Taxonomy of Viruses - searchable virus taxonomy, updated versions in 2007 and 2008.