Willpower to Keep Winning is still one of the bestselling pocketbooks on Amazon Japan in 2013

Daigo Umehara's semi-autobiography "Willpower to Keep Winning" is revealed to be one of the bestselling pocketbook of 2013 by Amazon Japan's bestsellers rankings.

• Bestselling Kindle book (e-book) of 2013 in pocketbook (nonfiction) category
• The 7th bestselling book (paper edition) of 2013 in pocketbook (nonfiction) category

Please note that the book was also the 7th bestselling pocketbook of 2012.