photo courtesy of: https://lizzie-borden.com/
Hawthorne Hotel - https://www.hawthornehotel.com/a-hotel-in-the-heart-of-salem-ma/
https://melmagazine.com/en-us/story/the-father-daughter-duo-who-found-the-truth-behind-a-string-of-century-old-murders - link to an article about the book, "The Man from the Train." Not about Elsie the ghost but about the Newton family murders that some have connected to the ghost Elsie, but really has nothing to do with her at all.
Photos of inside the buildings
Book on Amazon
List of books and articles on the subject