Authors
Mr. James
Selma Lagerlöf
Edgar allan poe
john bauer
Books
first two Witcher books
Trolldom : spells and methods of the norse folk magic tradition by Johannes Björn Gårdbäck and Draja Mickaharic
Norse Mythology: A Captivating Guide to Norse Folklore Including Fairy Tales, Legends, Sagas and Myths of the Norse Gods and Heroes by Matt Clayton
Damnable Tales: A Folk Horror Anthology by Richard Wells
"Lore of the Land" by Jacqueline Simpson and Jennifer Westwood.
Offerträdet (Sacrifical Tree) by Per Faxneld (dont know if its translated into English yet though)
Historia de Gentibus Septentrionalibus ("A Description of the Northern Peoples") by Olaus Magnus.
https://en.m.wikipedia.org/wiki/Gnomes_(book)
Asbjornsen & Mo
"Wolf Winter" and "In the Month of the Midnight Sun" by Cecilia Ekbäck
Through the Woods by Emily Carroll.