The relative luminous flux of a source was compared with a standard source.

The energy flux from Vega has been precisely measured against standard light sources.

Nobody had ever tried making a harbor this way before, although Antarctic icebergs were standard sources of fresh water.

The 12" disc gradually became the standard source of pre-recorded music and the 16" record disappeared.

Soft law is an important ancillary to these standard sources.

Her selection, along with the one by the Lambs, is still in print, and both are still considered standard sources.

However, Herodotus' writings are not used as a standard source by contemporary historians.

All other reagents were of analytical grade from standard commercial sources.

Soon, it became a standard source of weaponry for Roman Legions.

Steam power first appeared in the 1860s and became the standard source of power for over a century.