There are two of seven links which the SE Android app (ver 1.0.89) will not follow, but on Windows 10, both Firefox and Chrome do. They are in the Cool References section, numbered 3 and 4. See my answer to: Why does the Commodore C128 perform poorly when running CP/M?
My smartphone is a OnePlus 3 with Android version 7, OxygenOS version 4.0.3.
Item #3 is pretty complex, to a certain post from the usenet at Google Groups:
Link to Google Groups(embedded since the URL contains
$characters that break the markdown)
@AndrewT. provided working URL for this. The one I used was based on a search, but Andrew's link works fine in Android:
Item #4 is a lot simpler, but it's an FTP:
I do not know if these are bugs in the SE app or Android's net linkage. There is no problem accessing the PDF file linked near the top of my answer.