Generally, it's simply a sliding scale of voting vs non voting stock. AKA each share of class A get's 10 votes, Class B get's 1 vote, and Class C get's 0 votes. Which is equivalent to A is 10 voting shares, B is 1 voting share 9 non voting share, and C is 10 non voting shares.

Note, none voting shares get the same percentage of the profits. And often there are conditions that transform A shares into B shares upon sale etc.

That doesn't appear to be the meaning of "control" that OP is using.

Thanks for the suggestion! I'll see what I can pull together quickly.

Briefly, control is the percent of all possible outcomes in which a shareholder's vote decides the result of the shareholder-vote/election. Control is directly related to the odds of winning the shareholder-vote.

This is something like the Banzhaf power index, I think: http://en.wikipedia.org/wiki/Banzhaf_power_index