Protozoology - Hall, Richard P. (Richard Pinkham), 1900 -1969 (Prentice-Hall, 1953)

Quarterly journal of microscopical science (J. and A. Churchill [etc.], 1922)

Quarterly journal of microscopical science (J. and A. Churchill [etc.], 1923)

Quarterly journal of the Florida Academy of Sciences - Florida Academy of Sciences. (Florida Academy of Sciences, 1970)

Quarterly journal of the Florida Academy of Sciences - Florida Academy of Sciences. (Florida Academy of Sciences, 1972)

Radiation biology - Hollaender, Alexander, 1898 - (McGraw-Hill, 1954)

Radioisotopes in biology and agriculture, principles and practice - Comar, C. L. (Cyril Lewis), 1914 - (McGraw-Hill, 1955)

Recueil de l'Institut botanique (Université de Bruxelles) - Institut botanique Léo Errera. (Henri Lamertin, 1902)

Recueil des travaux botaniques néerlandais - Koninklijke Nederlandse Botanische Vereniging. (Société botanique néerlandaise, 1904)

Removal of nitrate by an algal system - California. Department of Water Resources. (For sale by the Supt. of Docs., U.S. Govt. Print. Off., Washington, 1971)

Removal of nitrate by an algal system; phase II - United States. Environmental Protection Agency. (For sale by the Supt. of Docs., U.S. Govt. Print. Off, 1971)