  We present a family of tri-partite entangled states that, in an asymptotical
sense, can be reversibly converted into EPR states shared by only two of
parties (say B and C), and tripartite GHZ states. Thus we show that bipartite
and genuine tripartite entanglement can be reversibly combined in several
copies of a single tripartite state. For such states the corresponding
fractions of GHZ and of EPR states represent a complete quantification of their
(asymptotical) entanglement resources. More generally, we show that the three
different kinds of bipartite entanglement (AB, AC and BC EPR states) and
tripartite GHZ entanglement can be reversibly combined in a single state of
three parties. Finally, we generalize this result to any number of parties.
