For anyone wondering about the illustrations (which are fantastic, great choice!) – it looks like most are public domain, by Kay Nielsen, from the book East of the Sun and West of the Moon (1914). https://publicdomainreview.org/collection/east-of-the-sun-and-west-of-the-moon-illustrated-by-kay-nielsen-1922-edition/
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That is correct! You can also find them here: https://commons.wikimedia.org/wiki/Category:Kay_Nielsen