Sibling Rivalry

The boys have progressed beyond accidentally inflicting injury on each other to full-on fighting. Oh dear. Based on my observations so far, Gus is usually the aggressor. I know, I know, you aren't supposed to "label" your kids. But what else am I supposed to say about it when he is literally throwing his weight around?? (He outweighs his brother by over a pound.)

Scenario:
Boys are playing with books. Gibson is flipping through the pages of one that Gus decides he wants to read. Gus grabs the book and turns aside to read it himself. Gibson cries.

What would you do in this situation? I've tried all of these:

A) Give the book back to Gibson and tell Gus, "Your brother is reading that book right now. You can have a turn when he's done." Then I give Gus a different book. Does it work? HAHAHA of course not! Two seconds later, Gus is back over there, grabbing the same book.

B) Let Gus keep the book he grabbed and give Gibson a different one. Does it work? Actually, most of the time, yes. I'm not sure if this means Gibson's more easy-going, more likely to cave in to bullies, or if he's just accepted the fact that his brother is the boss.

C) Use a different toy to distract them from books altogether. Does it work? About 40% of the time.

To keep the peace, we try to get two copies of toys when feasible. And I've actually seen some progress on the sharing front. We have this push walker that they used to really fight over - I had to hold one of them while the other one would take a turn or else it devolved into a knock-down-scream fest. But now, they can usually share it ok. It's like they keep an eye out for the walker to be available, and if brother is using it, they can find something else to play with while they wait. Oh, there is hope!

I'm trying to remember how my own parents handled it when my sister and I would fight. (Which we did. A lot.) I recall some toys being confiscated to the top of the refrigerator until we could agree to play with them nicely. I think once we were old enough, they expected us to work out our minor squabbles ourselves. Currently, I fear the injuries that will result if I leave my kids to resolve their own disagreements, since their main way of communicating disapproval is whacking brother in the head with the disputed item...