I thought I'd share a link that many will find helpful, as a follow up to the other thread questioning whether something is in the public domain. An important point to keep in mind any time you're talking about legal issues around your writing is that you should always research the matter yourself to make sure you're getting the right answer. Do not simply accept something you see posted in a forum - the advice is often wrong. Cornell University has a chart that they update yearly. It serves as a guide to determining the duration of copyright of various works. As you'll see from the chart, the analysis can get complicated. In many cases, where a copyright renewal was due, you can't answer the question of term/public domain without doing further research to find out whether the copyright was ever renewed when it was supposed to be. The majority of works were not renewed. As you'll see from the chart, in some cases there is other information you need, such as compliance with previously-required notice formalities, &c. Here's the chart: http://copyright.cornell.edu/resources/publicdomain.cfm
