You declare two ints, aval and valu
You then declare two references to integers. The references, "six" and "three" refer to the integers "aval" and "valu" respectively. A reference is just an "alias", which means that any changes to the reference also change the data it refers to.
Then you try to do output of "&six". The ampersand is the "address-of" operator, which means when you do this...
cout << &six
You are not printing the referenced data (aval), but the address-of the reference. Hence why you have an address printed.