TITLE: Where was it first stated that there are no 4-transitive finite groups other than symmetric, alternating and Mathieu groups?
QUESTION [8 upvotes]: It seems to be well-known that the six-transitive finite groups are the symmetric and alternating groups, and the only other four-transitive finite groups are the Mathieu groups (the statement can be found in Cameron's 1999 "Permutation Groups", p 110), but I can't seem to figure out where the result was first stated (Cameron is not much help, though he does give a vague sketch of how one might go about proving this result).

REPLY [5 votes]: Peter Cameron has an article "Finite permutation groups and finite simple groups. He states that Wielandt showed that any 6-transitve group is alternating or symmetric, given the Schreier's conjecture is true. Schreier's conjecture is that the outer automorphism group of a finite simple group is solvable, and the truth of this is a consequence of the classification.
I found Cameron's article by googling on "Wielandt Schreier". Wielandt's result was published as H. Wielandt, "Uber den Transitivitatsgrad von Permutationsgruppen", Math. Z. 74 (1960), 297-298.