This post by a British shaman speaks about how to stand in your own power. She doesn't mention the word "sovereignty" but that is what she is talking about. I would be interested to hear what you think about the article.

Learning to stand protected and whole in your own power is more than about guarding yourself with all the million-and-one methods of psychic protection available to the modern-day magical practitioner — from the Lesser Banishing ritual and the four pillars, to the blue translucent egg and the fiery pentagram to mention just a few. That’s because it’s no good using your intention to magically construct one of these energetic devices before setting off down the road if the first thing you’re then going to do is hand over your decision-making ability to the next person you meet at the bus stop just because they’ve got a bigger hat.
Even if they’re your boss, you have to learn to manage your power around them, and you will eventually get quite skillful in these sorts of situations.
But it’s best to start off small, at first. Don’t go straight for the might of the military-industrial juggernaut. Parity begins at home. Begin with your partner and your immediate friends and then watch as your whole life starts to transform. As you change the microcosm, the macrocosm will very often follow suit.