Coba jelasin Lihat pula dari Sistem Satuan Internasional dong

Redefinisi satuan pokok SI 2019

"The Current SI Seen From the Perspective of the Proposed New SI". Barry N. Taylor. Journal of Research of the National Institute of Standards and Technology, Vol. 116, No. 6, Pgs. 797–807, Nov–Dec 2011.

B. N. Taylor, Ambler Thompson, International System of Units (SI), National Institute of Standards and Technology 2008 edition, ISBN 1-4379-1558-2.