In the classical quasithin case of the quasithin theorem, if a group 
does not have a "strongly embedded" subgroup,
then 
is a group of Lie-type
in characteristic 2 of Lie rank 2 generated by a pair of parabolic subgroups 
and 
, or 
is one of a short list of exceptions.
Quasithin Theorem
See also
Lie-Type GroupExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Quasithin Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/QuasithinTheorem.html