43 CFR §20.101

In addition to the rules in this part, employees of the Department of the Interior also should refer to the Standards of Ethical Conduct for Employees of the Executive Branch, at 5 CFR part 2635; the Department's regulations that supplement those executive branch-wide standards at 5 CFR part 3501; the employee responsibilities and conduct regulations at 5 CFR part 735; and the executive branch financial disclosure regulations at 5 CFR part 2634.