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Some syntax clarification:
This is a short syntax tutorial for upcoming posts.

int *p; // a pointer to an integer
int &p; // a reference to an integer

const int *p; // pointer to a constant integer
int const *p; // same as above
int * const p; // constant pointer to an integer
const int * const p; // constant pointer to a constant integer
const int * const *p; // a pointer to a constant pointer to a constant integer

But references are implicitly constant, therefore,

int & const p; // is not allowed
const int & const p; // is not allowed

int (*q)[10] // a pointer to an array of 10 integers
int (&q)[10] // a reference to an array of 10 integers. Yes, they are supported.
int (*q)(char) // a pointer to a function
int (&q)(char) // a reference to a function

int *&q // A reference to a pointer to an integer. And this too is supported.
int (*&q)[10] // a reference to a pointer to an array of 10 integers.

Similar to passing integer by reference to change it inside a function,
consider using reference to pointer to change the pointer inside
a function.

Comments

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