file:///home/chronos/u-49450bb8bdf2afcff18d9ee71e5e0503a89360a8/MyFiles/Downloads/Majestic_12-UFO_Official_Manual.pdf
I tried this link (exactly as you posted) in 2 different browsers. The link as posted above doesn't connect to anything.
You may have to download this to read all of it:
https://www.scribd.com/document/367908749/som1-01-special-operations-manual-pdf