I recently did a book promotion for my R book in portuguese and it was a big sucess!
My english book is now being sold with the same promotion. You can purchase it with a 50% discount if you buy it on the 10th day of march. See it here. The discount will be valid throughout the week, with daily price increases.
If you want to learn more about R and its use in Finance and Economics, this book is a great opportunity.
If you liked the work (or not), please provide a honest review at Amazon.com. As an author, I certainly apreciate it and will use the feedback for the next edition of the book.