A fun riddle picture book series for young children, a complete set of 3 volumes. There was a pencil marking of the purchase date, which has been erased. A sticker from the Dohwakan subscription course (Okurumi Course) is affixed. There is a faint stain on the inside front cover of volume 2. List price: 638 yen + tax each - Series title: Riddle Picture Book - Volumes: 1, 2, 3 - Author: Hirotaka Nakagawa - Illustrator: Yukako Yamahara - Target age: Preschoolers - Language: Japanese Thank you for looking.