a person, book or document that provides information, especially for study, a piece of written work or news
منبع, ماخذ, مرجع
He refused to name his sources.
Government sources indicated yesterday that cuts may have to be made.
Intelligence sources say they now believe he is dead.
This information comes from a very reliable source.
According to industry sources, these prices are likely to rise.
Proper attribution of source material is extremely important.
see also primary source, secondary source