1. On the probable number of species of insects in the creation; together with descriptions of several minute Hymenoptera;Westwood;Magaz. Nat. Hist. J. Zool. Bot. Mineral. Geol. Meterol.,1833
2. The magnitude of global insect species richness;Gaston;Conserv. Biol.,1991
3. How many species are there?;Stork;Biodivers. Conserv.,1993
4. Tropical forests: their richness in coleoptera and other arthropod species;Erwin;Coleopt. Bull.,1982
5. How many species?;May;Philos. Trans. R. Soc. B,1990