Where are the intel manual x86-16?

I was studying the code for x86-16 operating systems(como DOS),with a desassembler, but I can’t find the intel manual on the intel website:

Searching on google, only unofficial sources.

Perhaps the manual is from 1979, and probably released in print, and they didn’t want to have work releasing on the internet? Or removed from the site for convenience to encourage x86-32 and x86-64 assembly programming?

Supposed manual: Intel 8086 Family User’s Manual October 1979.