The Coulter counter, originally designed for high-speed counting of blood cells, was used in this study for quantitative estimation of several species of unicellular algae. Tests of the instrument's reliability and the reproducibility of its counts have given satisfactory results. The instrument is also well suited for use in the study of growth curves of unicellular algae. The instrument's limitations and sources of error are discussed.
El-Sayed, Sayed Z., and Byung D. Lee. 1963. "Evaluation of an automatic technique for counting unicellular organisms." Journal of Marine Research 21, (2). https://elischolar.library.yale.edu/journal_of_marine_research/994