Modeling an arbitrary graph with reference counting immediately leads to the problem of cycles and the need of some form of GC to collect them. It is better to

Modeling an arbitrary graph with reference counting immediately leads to the problem of cycles and the need of some form of GC to collect them. It is better to use a GC from the start (not collecting things until the graph owner decides to discard the whole graph is often a useful approach), or reduce the graph to a tree and use weak references for references between branches. Or even use handles as advocated by the article, which essentially reduces the graph to an array and uses its indexes as weak references.