The Delta Society International- Commodities Div. 1991 Manual by J. Welles Wilder is a book focused on investing and proprietary trading history. Published by Trend Research in the United States, this illustrated 1st edition book is written in English and intended for adult education and business levels. The manual delves into the world of financial trading systems, providing insights and information for those interested in the field. With features such as being inscribed, this book is a valuable resource for individuals looking to deepen their understanding of trading systems. The Author J. Welles Wilder has signed the manual. Included is a Membership Agreement. The Delta System Phenomenon is used to predict stocks of 24 Commodities.