For more than 100 years Paris has been home to Le Grand K, a block of metal that defines the precise weight of a kilogram.
원문출처 : https://www.cnn.com/2018/11/13/world/kilo-measurement-scli-intl/index.html
원문출처 : https://www.cnn.com/2018/11/13/world/kilo-measurement-scli-intl/index.html