Entering "Wedderburn's Theorem" into Google gives the following:
http://planetmath.org/encyclopedia/W...nsTheorem.html
No place I looked I was able to find a proof to this theorem. What it states it that there is no such thing as a finite strictly skew field. And he proves it by showing if it is finite it is a field. Everything is easy to prove except commutativity (ironically this is usually the easiest to prove).
Entering "Wedderburn's Theorem" into Google gives the following:
http://planetmath.org/encyclopedia/W...nsTheorem.html