Particle Counts of Haemagglutinating Viruses Isaacs, A. and Donald, Heather B.,, 12, 241-247 (1955), doi = https://doi.org/10.1099/00221287-12-2-241, publicationName = Microbiology Society, issn = 1350-0872, abstract= The electron microscope was used to make particle counts of the viruses of Newcastle disease of fowls, fowl plague, mumps and influenza C. Two counting techniques previously described were also used, and correlations with simultaneous measurements of haemagglutination and infectivity were made., language=, type=