 Here are the links to Hubble sites, white papers and other locations where I found the information contained in this 2018 review. These are also the places where you can begin to do your own research. I want to also thank Jonathan Orsted for his great help editing these videos. And don't forget, every How Far Away Is It video, including this one, has a document with the text, pictures, links, and notes located on HowFarAwayIsIt.com slash documents. Thanks for watching!