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Revision of the genus Ischyrus Lacordaire (1842) (Erotylidae: triplacinae) of North and Central America - Skelley, Paul E. (1994)

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Revisionary studies in the Nearctic Decticinae - Birchim, James D. (Pacific Coast Entomological Society, California Academy of Sciences, 1968)

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Rhodora - Robinson, Benjamin Lincoln, 1864 -1935 (New England Botanical Club [etc.], 1985)

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Rod and gun - Canadian Forestry Association. (Rod and Gun Pub. Co. [etc.], 1918)

Rural New Yorker - Moore, D. D. T. (Rural Pub. Co. [etc.], 1859)

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Seven years' travel in Central America, northern Mexico, and the far West of the United States - Fröbel, Julius, 1805 -1893 (R. Bentley, 1859)