LVars are one of my favorite concepts, and they have roots in Vijay Saraswat's thesis on concurrent constraint programming, which is parametric over a choice of lattice. I second the recommendation for the LVars series of papers, and I also highly recommend digging up a copy of Saraswat's thesis work, which was published as a book. https://mitpress.mit.edu/books/concurrent-constraint-program...

The semantics of determinate CCP programs (and by extension, LVars programs) can be described really beautifully in terms of closure operators on the underlying domain. I'm not sure this made it into the initial published thesis, but this is an accessible paper on the topic: http://www.lix.polytechnique.fr/comete/stages/references/ccp...