[see also: retrieve
If we know a covering space E of X then not only do we know that......, but we can also recover X (up to homeomorphism) as E/G.
Thus F can be recovered from XkF by k-fold integration.
Replacing f by log f, we recover the theorem of .
This is nearly the same as formula (6) of , which we can recover by multiplying (2.3) by F(s).