"REFERENCES." Oxford Scholarship Online. 2007-09-01. Oxford University Press. Date of access 20 May. 2013, <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198511748.001.0001/acprof-9780198511748-bibliography-1>.
(2007-09-01). REFERENCES. Oxford Scholarship Online. Retrieved 20 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198511748.001.0001/acprof-9780198511748-bibliography-1.
"REFERENCES." Oxford Scholarship Online. 20 May. 2013. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198511748.001.0001/acprof-9780198511748-bibliography-1.
REFERENCES. In: Gabbay DM, Maksimova L. Interpolation and Definability: Modal and Intuitionistic Logics. Oxford University Press; 2005. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198511748.001.0001/acprof-9780198511748-bibliography-1. Accessed May 20, 2013.