Referencing duplicates from other objects

1

…is there a way to do it? If so, say I have two movie clips A and B, and I’ve made duplicates of A. How can I reference each A from:

  1. Any of the other A duplicates? and
  2. The B movie clip?

What is the scoping syntax for that? I tried to use _root.{the name of A duplicate}.{property} for accessing A from B but it didn’t seem to work.