Why cant I find any information on this 11 digit isbn number inside my book?
As I said on the discussion board, the doubled 4 is a typo. Remove it, and you’ll have a valid ISBN. For what it’s worth, I figured this out by knowing how to calculate the “check digit” (ie, the last digit of the ISBN), and assuming that the first and last digits were correct as stated. Removing one of the fours makes a valid ISBN. I then did a Google search for the result, and found your book. (fwiw, to calculate a valid ISBN, multiply the first digit by 10, the next by 9, etc, down to the last one by 1. Add each product. The result must be a multiple of 11. Removing one of the fours is the only removal that results in a valid ISBN) Sources: http://en.wikipedia.org/w/index.php?
As I said on the discussion board, the doubled 4 is a typo. Remove it, and you’ll have a valid ISBN. For what it’s worth, I figured this out by knowing how to calculate the “check digit” (ie, the last digit of the ISBN), and assuming that the first and last digits were correct as stated. Removing one of the fours makes a valid ISBN. I then did a Google search for the result, and found your book. (fwiw, to calculate a valid ISBN, multiply the first digit by 10, the next by 9, etc, down to the last one by 1. Add each product. The result must be a multiple of 11.
