The Stanford Encyclopedia of Philosophy (SEP) combines an online encyclopedia of philosophy with peer reviewed publication of original papers in philosophy, freely accessible to Internet users. It is maintained by Stanford University. Each entry is written and maintained by an expert in the field, including professors from many academic institutions worldwide. Authors contributing to the encyclopedia give Stanford University the permission to publish the articles but retain the copyright to those articles. The SEP has 1,502 published entries. Apart from its online status, the encyclopedia uses the traditional academic approach of most encyclopedias and academic journals to achieve quality by means of specialist authors selected by an editor or an editorial committee which is competent (though not necessarily a specialist) in the field covered by the encyclopedia and peer review.