title: Electron microscopic observations on the development of variola virus in chick embryo chorioallantoic membrane cells.
mesh_terms: D000818:Animals; D002642:Chick Embryo; D005321:Extraembryonic Membranes / Q000166:cytology; D008722:Methods; D008854:Microscopy, Electron; D012901:Variola virus / Q000254:growth & development*