A primary source. That would be a source coming directly from someone who was in the war so you know it is reliable and probably the most accurate. A secondary source could be from a journalist or an outside mind that doesn't know the true experience of being in the war and is just observing from an outsiders view.
On a certain day, the isobars on a weather map are very close together over eastern Kentucky. To make the people of this area aware of possible risk to life and property in this situation, the National Weather Service should issue A HIGH WIND ADVISORY
