I has some issues with the definition of the affine map. I remember I've read somewhere that the author defines an affine map as
Let $V,W$ be vector spaces over a field $K$ and a map $f:\ V\longrightarrow W$. Then $f$ is called an affine map if there exists a linear (bijective) map $T:\ V\longrightarrow W$ and a vector $w\in W$ such that $$f(x)=T(x)+w,\ \forall x\in V.$$
But I can't tell which material I read that from. I tried finding some books on affine geometry, but their's definitions on the affine map is kind of different to what I know.
Do you know any book/material in which the definition of affine map is something like what I stated above ? Thanks