Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades. - Bragstad, Karoline; Martel, Cyril J.; Thomsen, Joakim S.; Jensen, Kim L.; Nielsen, Lars P.; Aasted, Bent; Fomsgaard, Anders (Influenza & Other Respiratory Viruses, 2011)