QR codes for reviews

I am not totally sure if this is already available because I am just on the manuscript section so far. In "escape the 9 to 5" the twins added a page in the middle of the book with a link to take the reader to the review page for the book. This only works for the ebook, though. If there was a QR code on that same page that the print copy readers could use to take them to the review page on their phone we could get more reviews.