Schrick, Livia; Tausch, Simon H; Dabrowski, P. Wojciech; Damaso, Clarissa R; Esparza, José; Nitsche, Andreas (2017). “An Early American Smallpox Vaccine Based on Horsepox”. New England Journal of Medicine377 (15): 1491–1492. doi:10.1056/NEJMc1707600. PMID29020595.
Schrick, Livia; Tausch, Simon H; Dabrowski, P. Wojciech; Damaso, Clarissa R; Esparza, José; Nitsche, Andreas (2017). “An Early American Smallpox Vaccine Based on Horsepox”. New England Journal of Medicine377 (15): 1491–1492. doi:10.1056/NEJMc1707600. PMID29020595.