Sources:

https://www.latimes.com/archives/la-xpm-1992-12-05-mn-1143-story.html

 

http://truecrimediscussions.blogspot.com/2015/07/matthew-heikkila.html 

 

https://www.orlandosentinel.com/news/os-xpm-1991-02-02-9102020729-story.html 

 

https://apnews.com/145634b7cd76007d4b65fe9f798c1182 

 

“The Dark Son,” by Denise Lang

 

ID Channel: Your Worst Nightmare: Season 1, Episode 5 “The Bad Son”