Baugh, Albert C; & Cable, Thomas. (1993): , 4. utg., London: Routledge. Blake, Norman (1992): . Cambridge: Cambridge University Press. Baker, Peter S., , Oxford 2003, ISBN 0-631-23454-3. Campbell, A. (1959): . Oxford: Clarendon Press. Cercignani, Fausto, , Journal of English and Germanic Philology 82 (1983), 313-323. Earle, John (2005): . Bristol, PA: Evolution Publishing. ISBN 1-889758-69-8. (Gjenutgivelse av 4. utg, 1877–1902) Hall, J. R. Clark - Merritt, H. D., , Cambridge 1969. Hockett, Charles F., , Language 35 (1959), 575-597. Jespersen, Otto, , Copenhagen 1909-1949. Kuhn,Sherman M., , Language 37 (1961), 522-538. Lass, Roger, , Cambridge 1994, ISBN 0-521-43087-9. Mitchell, Bruce - Robinson, Fred C., , Oxford 2001, ISBN 0-631-22636-2.