In 1.05, you are allowed to build improvements on resources even if they are outside of your zone of control if they are adjacent to one of your cities.
An Ancient Library that was outside my zone of influence but adjacent, would allow me to contruct it (paying 5 materials). But no matter how many times I loaded the game and tried different things (no building orders in the city, different bulding orders...), as soon as I hit End Turn, the Ancient Library would stop building and I would not get my materials back. It would allow me to try to build it again but same results.
I'll try to repeat it again. Especially because I overwrote the saved game by accident.