This article is about longitude and latitude; see also UTM coordinate system Map of Earth showing lines of latitude (vertically) and longitude (horizontally); large version (pdf) The geographic (earth-mapping) coordinate system expresses every horizontal position on Earth by two of the three coordinates of a spherical coordinate system which... Emi Koussi is a high volcano that lies at the south end of the Tibesti Mountains in the central Sahara of northern Chad. ...
References
Siebert, L. and T. Simkin (2002-). Volcanoes of the World: an Illustrated Catalog of Holocene Volcanoes and their Eruptions. Smithsonian Institution, Global Volcanism Program Digital Information Series, GVP-3. URL: http://www.volcano.si.edu/world/