![nimi](https://ellsa.ee/wp-content/uploads/2021/01/Oster-Vallatu-matemaatika.jpg)
- Illustrator: Ulla Saar
- Translator: Ilona Martson
- Language: Estonian
- Varrak
- 2015, 107 pp
- ISBN: 9789985335611
- non-fiction, storybook
- Age: 10+
2015 25 Best Designed Estonian Books, Certificate of Merit
2015 Good Children’s Book
2015 Good Children’s Book