The instructions, per the IRS, are as follows:
Carryback claim—credits and other losses. Enter “Carryback Claim” at the top of page 1 of Form 1040X. Attach copies of the following.
Both pages of Form 1040 and Schedules A and D, if applicable, for the year in which the loss or credit originated. Enter “Attachment to Form 1040X—Copy Only—Do Not Process” at the top of these forms.
Any Schedules K-1 you received from any partnership, S corporation, estate, or trust for the year of the loss or credit that contributed to the loss or credit carryback.
Any form or schedule from which the carryback results, such as Form 3800, General Business Credit; Form 1116, Foreign Tax Credit (Individual, Estate, or Trust); Form 6781, Gains and Losses From Section 1256 Contracts and Straddles; Form 4684, Casualties and Thefts; or Schedule C or F (Form 1040).
Forms or schedules for items refigured in the carryback year, such as Form 6251, Alternative Minimum Tax—Individuals; Form 3800; Schedule A (Form 1040); or Form 8962.
https://www.irs.gov/pub/irs-prior/i1040x--2017.pdf
