That's not an 'authorized' site? Published by the Department of Consumer Affairs with the relevant statutes and court cases noted at the end of each section?
Looking quickly through that site, and trying to understand your situation, it seems like your roommates are not on your lease with your landlord, so they are subtenants. This may or may not be against your lease. They are not responsible to your landlord for the rent, they are responsible to you. You still gotta pay the rent even if they don't since they aren't on the lease. Getting the rent from them is a matter of what agreement you have with them -- hopefully something written.
Look at
this section.
Standard disclaimer: IANAL, but I can read.
You could always look up the
laws yourself.
I had problems with my roommates a few months ago and couldn't find any site on the net that gave definitive answers. They won't exist, because no lawyer is going to give away legal advice for free. You're going to have to scour that Landlord Tenant handbook and the applicable statutes yourself and try to figure something out. In the end, I worked through the troubles with my roommates and I've just decided to stay until the lease runs out.
Maybe you can get a free 1/2 hour consultation from a lawyer to figure out what you can do.