Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Amazon Should Give Copyright Dates

There is a big problem with buying a book online when you can't see the copyright date. The advances and changes in the renewable energy field are happening very quickly. This book is a pleasant reminder of what things were like years ago, and they did a good job of it. I'm angry with Amazon for not revealing the date of publication. I would not have bought this "dated" book if Amazon had revealed when it was written.