They're the main two publications with the "Moderný Pračlovek" series (Modern Caveman). The principle idea was to signify caveman drawings inside a very simple way and items that had been used at that time... and also within our days. The very first a single — “Kuchyňa Pračloveka” (Caveman's Kitchen) — https://maplepublishers.com/blog/5-tips-to-find-the-best-self-publishing-companies-uk/