Analysis of information sources in references of the Wikipedia article "سرعت نور" in Persian language version.
... the most accurate standard for the metre is conveniently defined so that there are exactly 299,792,458 of them to the distance travelled by light in a standard second, giving a value for the metre that very accurately matches the now inadequately precise standard metre rule in Paris.
{{cite book}}
: |volume=
has extra text (help){{cite book}}
: |volume=
has extra text (help){{cite book}}
: |volume=
has extra text (help){{cite book}}
: |volume=
has extra text (help)