  We prove several results on Almgren's multiple valued functions and their
links to integral currents. In particular, we give a simple proof of the fact
that a Lipschitz multiple valued map naturally defines an integer rectifiable
current; we derive explicit formulae for the boundary, the mass and the first
variations along certain specific vector-fields; and exploit this connection to
derive a delicate reparametrization property for multiple valued functions.
These results play a crucial role in our new proof of the partial regularity of
area minimizing currents.
