greatest mysteries ufos

https://www.bellinghamherald.com/news/local/article85417412.html
https://en.wikipedia.org/wiki/Roswell_UFO_incident
https://medium.com/@Strange_bt_True/top-3-most-famous-ufo-sightings-in-history-6de38e201e60
http://www.ghosttheory.com/2016/01/18/the-night-a-ufo-landed-in-levelland-texas
http://www.sandiegouniontribune.com/opinion/the-conversation/sd-navy-pilot-ufo-20171218-htmlstory.html