Nº Enlace Autor
1

url CODATA Internationally recommended values of the Fundamental Physical Constants

http://physics.nist.gov/cuu/Constants/index.html

Andrés Meza

4 Mar 200504/03/052005-03-04
2

url The International System of Units (SI)

http://www.bipm.org/en/si/

Andrés Meza

4 Mar 200504/03/052005-03-04