article: International System of Units
links: Planck constant Liberia 1789 British Empire French language Avogadro constant National Bureau of Standards France Paris Boltzmann constant SI prefix 1971 William Thomson Newton (unit) 1860s United States Melting point James Clerk Maxwell SI base unit National Institute of Standards and Technology Power (physics) Physical quantity Washington, D.C. Symbol International Bureau of Weights and Measures Stress (physics) Central Intelligence Agency Force (physics) 1954 Mole (unit) French Revolution Siemens (unit) Meridian (geography) Mechanical work CGPM 20th century SI derived unit Myanmar Avogadro's number