Geodesic
Exceptional action of the simple groups $L_4(q)$ in the defining characteristic
Sibirskie èlektronnye matematičeskie izvestiâ, Tome 5 (2008), pp. 68-74 
A. V. Zavarnitsine. Exceptional action of the simple groups $L_4(q)$ in the defining characteristic. Sibirskie èlektronnye matematičeskie izvestiâ, Tome 5 (2008), pp. 68-74. http://geodesic.mathdoc.fr/item/SEMR_2008_5_a7/
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Voir la notice de l'article provenant de la source Math-Net.Ru

We find a counterexample to Problem 14.60 from the Kourovka notebook by giving an example of a group $\rm {PSL}_4(q)$ which is not recognizable among its covers from spectrum. Namely, we show that such a group has a module in the defining characteristic with the property that the element order set of the corresponding semidirect product equals that of the group itself.

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