ISO 4217 added to the standard. A number of currencies are not included in ISO 4217, because these currencies are: (a) minor currencies pegged 1:1 to a larger currency, even if independently regulated (b) a legal tender only issued as commemorative banknotes or coinage, or (c) a currency of an unrecognized or partially recognized state. These currencies include: See for a list of all currently pegged currencies. Despite having no official recognition in ISO 4217, the following non-ISO codes are sometimes used locally or commercially. In addition, GBX is sometimes used (for example on the London Stock Exchange) to denote Penny sterling,
International Standard Atmosphere International Standard Atmosphere The International Standard Atmosphere (ISA) is a static atmospheric model of how the pressure, temperature, density, and viscosity of the Earth's atmosphere change over a wide range of altitudes or elevations. It has been established to provide a common reference for temperature and pressure and consists of tables of values at various altitudes, plus some formulas by which those values were derived. The International Organization for Standardization (ISO) publishes the ISA as an international standard, ISO 2533:1975. Other standards organizations, such as the International Civil Aviation Organization (ICAO) and the United States Government, publish extensions or subsets