|Katina Davis Customer Service Representative
Thanks for bringing this to our attention! I've done a bit of looking around, and it seems that this is one of our older products and the difference in paper stock was the same across all of the books. From what I can tell, I believe that we had either tried a different printer or a different paper stock for the printing. So while it is a bit different, it is not a misprint and it shouldn't affect the quality of the book.
I hope this helps! Please let me know if there are any further questions or concerns that you may have, and I'll be glad to help out as best I can.