Sources:

https://unsolvedmysteries.fandom.com/wiki/Amy_Mihaljevic

https://www.news5cleveland.com/news/amy-mihaljevic-murder/possible-suspect-may-have-called-amy-mihaljevic-prior-to-her-disappearance-in-1989

https://www.cityofbayvillage.com/425/Amy-Mihaljevic-Case

https://www.news5cleveland.com/news/amy-mihaljevic-murder/exclusive-court-documents-reveal-startling-new-developments-in-amy-mihaljevic-murder-investigation

https://www.cleveland19.com/2021/10/26/now-we-know-new-clues-amy-mihaljevic-case/

"Amy: My Search for her Killer: Secrets and Suspects in the Unsolved Murder of Amy Mihaljevic" by James Renner. (Book)