If you want to contact the copyright owner regarding use of a copyrighted work, the best place to start is with the work itself. Copyright notices in published works identify the owner at the time the work was published. However, copyright ownership may have changed since publication. The copyright notice and any permissions are often printed on the back of the title page in books. Most owners will be apparent, particularly for relatively current works. However, identifying the specific owner may be more difficult for journal articles, gray literature and older works. Affiliation of the author may suggest ownership or may help to locate the individual author, but is not in itself definitive. The U.S. Copyright Office provides some suggestions in Copyright Office Circular 22.