2 U.S. Code § 6111
2 U.S. Code § 6111 is about Compensation of President pro tempore of Senate. It is under Subchapter II (Vice President and President Pro Tempore) of Chapter 61 (Senate Leadership) of Title 2 (The Congress) of the Code.
Whenever there is no Vice President, the President of the Senate for the time being is entitled to the compensation provided by law for the Vice President.