APA (7th ed.) Citation

Curds, C. R. (1969). An illustrated key to the British freshwater ciliated protozoa commonly found in activated sludge. H.M.S.O..

Chicago Style (17th ed.) Citation

Curds, Colin Robert. An Illustrated Key to the British Freshwater Ciliated Protozoa Commonly Found in Activated Sludge. London: H.M.S.O., 1969.

MLA (8th ed.) Citation

Curds, Colin Robert. An Illustrated Key to the British Freshwater Ciliated Protozoa Commonly Found in Activated Sludge. H.M.S.O., 1969.