A new law in California, signed on Tuesday by Gov. Jerry Brown, will require textbook publishers to describe the changes in new editions to professors and buyers. The legislation, sponsored by State Sen. Ellen Corbett, will take effect in 2013. According to the Associated Press, Senator Corbett, a Democrat, says the required information will help students determine whether they really need to buy an expensive new version or if a previous edition will suffice. Publishers will also be required to tell buyers about other products they offer on the same topic.