An unidentified source ignited the gas and caused the explosion.

The source then might cause harm to humans or the environment.

But that doesn't necessarily mean these sources couldn't have caused the conflagration.

The source then might cause harm to humans.

Only one immediately available source does not cause global warming, and that is nuclear energy.

Even then, he said, a natural source could cause a cluster of cases.

The research identifies which sources are causing the greatest damages.

You can see in the sample that light sources cause huge halos, and there isn't much edge sharpness or detail.

D denotes the extent to which a source could, if not under control, cause severe harm.

These sources of error add up and cause the telescope to point far from the desired object.