From Pub 559

Form 1310, Statement of Person Claiming Refund Due a Deceased Taxpayer. Form 1310 doesn't have to be filed if you are claiming a refund and either of the following applies to you.
• You are a surviving spouse filing an original or amended joint return with the decedent.
• You are a court-appointed or certified personal representative filing the decedent’s
original return and a copy of the court certificate showing your appointment is attached to the return.