What I do say: according to what I’ve read, history mischaracterizes the beliefs of people at and before the time Columbus regarding the shape of the earth’s surface.
What I don’t say: what you should think about the shape of the earth’s surface.
The books I mention are:
Great Soul of Siberia by Sooyong Park
An Indomitable Beast by Alan Rabinowitz
Magicians of the Gods by Graham Hancock