The book "The Dancing Goddesses" goes into great depth about the Slavic pagan calendar. It's a nice resource for other folklore too:
https://www.amazon.com/Dancing-Goddesses-Folklore-Archaeology-European/dp/0393348504
slavic traditions and mythology by stefan cvetkovic is really good
There's a book about Eastern European embroideries, but unavailable now on Amazon (I should have gotten it back in the day!): https://www.amazon.com/Goddess-Embroideries-Eastern-Europe-Kelly/dp/092902124X
Also, the Ukrainian Museum in NYC did a show, with the theme of Goddess in embroideries, which was scoffed at by Ukrainian Christians (like some of my fam); I never saw the show, but ordered the book, but it may have gotten lost in some moves (some of my books are currently in storage, so I don't know if I still have it). It was mostly re: Mokosh.
Well, the basic books in Czech are Svět slovanských bohů by Váňa, Encyklopedie slovanských bohů a mýtů by Profantová and Profant. Scans of these twoo books are available on uloz.to. There is also new Czech edition of book Mytologie Slovanů by Polish author Alexander Gieysztor.
Greetings from Slovakia!
Balkan Tradional Witchcraft by Radomir Ristic. I havent finished reading it but was interesting what U read.
Balkan Traditional Witchcraft https://www.amazon.ca/dp/0979616859/ref=cm_sw_r_u_apa_glt_i_CG8GC22HMFC0Y0D6VM8R?_encoding=UTF8&psc=1
"Witchcraft in Early Modern Poland" by Wanda Wyporska, you can read more about her & her books here: https://witchcraftinpoland.com/#:~:text=Poland's%20witchcraft%20persecution%20has%20long,of%20witchcraft%20trials%20in%20Wielkopolska.&text=Most%20assume%20that%20witches%20were,'feisty'%20women%20speaking%20out.
I believe this is what she studied. She provides a true account of the real history of witchcraft in Poland! Honestly amazing how she compiled all these artifacts into one book and I think she has more coming out. It's an easy to understand read while also painting a picture of what Poland's roots were really like. Highly highly recommend!
Here is the Amazon link to her book: https://www.amazon.com/dp/0230005217/ref=cm_sw_r_cp_apa_i_uXGlFbVMSG237
I see it's a little pricy now (I definitely paid less than this), although I bought this book last year. Hope this helps!