display the dates in two cells in a single cell separated by hyphen

hi,

i need the dates in 2 different cells to be combined in one cell separated by hyphen and display the same.

i tried in a3 "=a1 & a2" it is giving some numbers
example:
in cell a1 03-mar
in cell a2 04-mar
now in cell a3 i need 03-mar - 04 mar

thanks in advance
Girish