How do I use "both" with someone who is a doctor and professor?

Question

I would like to know if a person is a doctor and a professor, how should I address that person in writing?

• “Doctor and Professor”
• “Doctor/Professor”

Can I use “both” to say what their professions are?

• He is both doctor and professor

Answer 1

He's both a doctor and a professor.

is OK, but

He's a both doctor and professor.

is an error.
That is, "both" could only be used in a statement, but not a title.