Conditions under which the special orthogonal group $\text{SO}_{p,q}$ is quasi-split A reductive group $G$ is quasi-split if it has a Borel subgroup defined over the underlying field. 
Let $\text{SO}_{p,q}$ be the special orthogonal group of type $(p,q)$.
I vaguely remember that there is a statement in the spirit of:
"If $\vert p-q\vert$ is smaller than $K\in\mathbb{Z}$, then $\text{SO}_{p,q}$ is quasi-split."
Do I remember correctly? And if so, what is the correct value of $K?$ Furthermore, a reference for a proof of the fact will be much appreciated.
EDIT It seems my memory was correct and it is $K=3$: In D. Prasad's lecture notes the statement
$$\text{"The group $\text{SO}(p, q)$ is quasi-split if and only if $|p − q| ≤ 2$."}$$
is given without proof or further explanation. I'm still interested in a good (non-lecture notes) reference (i.e. a book or paper) or a proof for this fact.

Copied from MO. First of all, a group is quasi-split iff its Satake diagram does not contain black dots. The list of Statake diagrams can be found in many places but most of them are difficult to understand out of context. Of the more useful kind are the tables in
Onishchik, A. L.; Vinberg, Ėrnest Borisovich (1994), Lie groups and Lie algebras III: structure of Lie groups and Lie algebras
For the theory, I found Section 29 of Daniel Bumps book on Lie groups quite useful (see in particular p. 294ff)
