There is also this paper by Bacon et al that develops a framework that shows the relationship between refcount and tracing GC (duals of each other) plus the var

There is also this paper by Bacon et al that develops a framework that shows the relationship between refcount and tracing GC (duals of each other) plus the various optimizations of the two: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.143.6619 http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.143....