Citation Rowlinson P (1976) On (1, 6)-Groups. Journal of the London Mathematical Society, s2-14 (3), pp. 481-486. https://doi.org/10.1112/jlms/s2-14.3.481
Abstract First paragraph: A (∫,ƒ)-group is a transitive permutation group (G, Ω) of even order such that ∫ is the maximal number of points of Ω fixed by an involution of G. The object of this note is to show that a Sylow 2-subgroup of a simple (1, 6)-group has either (a) sectional rank at most 4 or (b) order at most 29.
Journal Journal of the London Mathematical Society: Volume s2-14, Issue 3
Oxford University Press for London Mathematical Society