- Hope Entomological Library, Oxford University Museum of Natural History: ARW 79
- Hope Entomological Library, Oxford University Museum of Natural History: ARW 79
- Marchant, J. (Ed.). (1916). In: Alfred Russel Wallace; Letters and Reminiscences. Vol. 2. London & New York: Cassell & Co. [p. 79]
How Poulton has gathered facts proving the non-heredity of acquired characteristics. About collecting. Mentions Birch.