You did not add much code to clarify, but as it is written it looks like a function declaration - in that case it makes sense.
Defining a parameter as & in a c++ function declaration means that the parameter is passed by reference, as in the next example
void same(int &n); int main(){
int iA = 5; same(iA); cout << iA; return 0; }
void same(int &n){
n = 6;
}
So by passing a parameter as &*response_ I'm passing
a reference to the object pointed by response_.
I hope I have been clear enough (English is not my primary language) and to have helped you.
EDIT: I found an article on CodeProject
Pointer to Pointer and Reference to Pointer[
^], maybe it helps you.
- Denis