This is a critical source of water for the district, compromised by silting.

The property tax is a critical source of revenue for the city.

The Internet has already become a critical source of health-care and medical information.

Second, broadcast outlets are still primary, critical sources of information for the American public.

Pennsylvania was a critical source of raw materials to the Union war effort, particularly anthracite coal.

These sectors, especially energy, are a critical source of tax revenue for the Russian Government.

The buying comes as several critical sources of industry growth are slowing.

Too much control can be a bad thing, particularly when innovation is a critical source of competitive advantage.

The social group is a critical source of information about individual identity.

And many activities do little, if anything, to strengthen the back's most critical source of support: the abdominal muscles.