Don't get lost with this helpful guide: Statistics by Mana Takahashi Gijutsu Hyoronsha I purchased this book, but I didn't use it in class. I couldn't find any writing or folds. In the third photo, there is a black stain on the bottom of the book from when I purchased it. Please note that there may be oversights due to my amateur inspection. The color may differ from the actual product. This is a used item stored at home. I would appreciate it if you could understand this before purchasing. If you have any concerns, please feel free to comment. Instant purchase is welcome. Search from #Lemonen_shop (^^)