Vol 25 (1988) - Original Articles
CHARACTERIZATION O F SOME BIOLOGICAL MARKERS AND ANTIGENIC STRUCTURE OF INFLUENZA VIRUSES TYPE A ISOLATED DURING THE PERIOD 1986-1987 IN SEVERAL DISTRICTS OF NORTH-EASTERN BULGARIA AbstractPDF
Vol 22 (1985) - Original Articles
ON SOME BIOLOGICAL PROPERTIES OF INFLUENZA VIRUSES TYPE A ISOLATED DURING THE PERIOD 1981-1983 AbstractPDF