Scientific names are given to avoid confusion, indicate relationships, such as genetic, ecologic, and physiologic, and act as reference sources in scientific communication and literature. Scientific names are given to organisms in accordance with internationally accepted rules. In the case of plants, the naming process is governed by the rules of the International Code of Nomenclature for Algae, Fungi and Plants (ICNafp). The binomials are also known as binary combinations. It was the Swedish botanist Carolus Linnaeus who established the binomial and trinomial systems of plant nomenclature. As the discovery of new species increased exponentially, the polynomial system proved difficult for remembering and indexing plant names. Subsequently the polynomials were superseded by the binomial system. Tautonym is a binomial in which the genus name and specific epithet are spelled identically and is not permitted in the ICNafp.