Details of all the jointly approved systems are outlined in the National Geospatial-Intelligence Agency publication Romanization Systems and Policies (2012), which superseded the BGN 1994 publication Romanization Systems and Roman-Script Spelling Conventions. Romanization systems and spelling conventions for different languages have been gradually introduced over the course of several years. The currently used set is available on the UK government site.Romanization systems - GOV.UK Guidance on the US Board on Geographic Names (BGN)/Permanent Committee on Geographical Names (PCGN) romanization systems. A complete list of BGN/PCGN systems and agreements covering the following languages is given below (the date of adoption is given in the parentheses). The status "agreement" refers to systems which were created by authorities of the corresponding nations and then adopted by BGN and PCGN.
