Instruct: Classify Amazon reviews into positive or negative sentiment
Query: The Ultimate Reference Source for Collectors of Mysteries

Ms. Heising has done it again! In addition to a useful tool for the mystery reader, this book is the very best source for the collector of first edition mysteries. Series are listed by date of publication, and indications are provided for those titles which have been nominated or have won major prizes in the mystery genre. No serious collector can be without this resource on their shelf for its thorough research capability (and no serious "book scout" can be without its counterpart Pocket Guide - available separately - for on-the-road portability). As a librarian and a collector, I believe that this is the very best work in the field. So if you are a reader who is thinking also of collecting, or a collector who also reads, don't even think about it - buy this book.