This issue has been forged a lot. One easy thing
is to compare the cancellations with those on the
Carol issue  - these six are easily detected as
forgeries on those grounds.

More possible characteristics:
Forgeries of 2b and 5b has the same gitter ornament behind
POSTA, ROMANA, FRANCO etc as 20b
Originals has a more complex pattern
 
Left = Original, Right = Fake
note also: dot under S

The forgerers has had some difficulties with the beard.

Both 5b issues have a blue line (cut-throat) under
the beard instead of shadings.
The 20b has rounded beard instead of pointed,
and extra strong lines on the throat.

And finally - complete sheets....
2 parale 5 parale 5 parale 20 parale
but, wait a minute - a complete sheet is
192 stamps for the 2 and 5 parale, 200 stamps for the 20 parale. Some are missing..