In the his book


*Linear algebraic groups*, by T.A. Springer,


there is a list of possible Tits-Indexes. For the $E\_7$ case, there is an index shown, such that vertex $1$ and $7$ are circled (Bourbaki notation). I just realized that yesterday by coincidence. However in Tits's original paper this index is not listed. On top of that neither here


<http://arxiv.org/pdf/1511.02538.pdf>


nor here


<http://arxiv.org/abs/0807.2140>


do we find it.


What did go wrong in Springers book? 



Wrong Tits-Index of E7 from Springer 's book
That is a typo. In index 14 on p. 321 the vertex 6 should be black. In Proposition 17.8.2, this index is correct. It corresponds to $E\_{7,3}^{28}$ in Tits' notation.


