| title | ISBN-13 | year of publication |
|---|---|---|
| Nauka jest prosta | 978-83-7442-508-7 | 2008 |
| Science Is Simple | 978-1-4178-0914-1 | 2003 |
| Science Is Simple: Over 250 Activities for Preschoolers | 978-1-4587-5757-9 | 2010 |
| Science Is Simple: Over 250 Activities for Preschoolers | 978-0-87659-272-4 | 2003 |
Gryphon House · Jednosc · ReadHowYouWant · San Val