I am afraid this is not the answer, copyright laws varies and is complicated according to the country and to the situation. If this is the answer, under what circumstances? What are the precedents to support your answer.
As long as it is not copyrighted you should be fine as long as you quote your source... It may be easier to just write your own material or have someone write it for you.
Ok here is more question ? What if we rewrite the content with rewrite software and the result is 100% unique and copyscape passed . Their are so many services on dp , so this means we can buy such software and rewrite any pro blogger article and publish it . If result of rewrite articles are passed by copyscape than the blogger can't claim ownership on them .