Fossil evidence demonstrates the existence of swifts during that period in Europe.

Attempts to demonstrate the existence of a "brown note" using sound waves transmitted through air have failed.

Several other books also demonstrate the existence of sundown towns.

Some commentators consider him the first to demonstrate the existence of biological stress.

The courts have recently demonstrated the existence and effectiveness of that power.

This is already enough to demonstrate the existence of transcendental numbers.

However, the scientific literature has failed to demonstrate the very existence of the subluxation.

In 1931, he and his associates went on to demonstrate the existence of heavy water.

On April 25 a mass plot was published that demonstrates the existence of these molecules.

Studies to demonstrate the existence of language have been difficult due to the range of possible interpretations.