Gaunt, MW; Miles, MA; (2002) An insect molecular clock dates the origin of the insects and accords with palaeontological and biogeographic landmarks. Molecular biology and evolution, 19 (5). pp. 748-61. ISSN 0737-4038 https://researchonline.lshtm.ac.uk/id/eprint/16251 Full text not available from this repository.