20 C.F.R. § 216.64
What is required for payment
An eligible widow(er), surviving divorced spouse, or remarried widow(er) must:
(a) Apply to be entitled for an annuity; and
(b) Submit evidence requested by the Board to support his or her application.
An eligible widow(er), surviving divorced spouse, or remarried widow(er) must:
(a) Apply to be entitled for an annuity; and
(b) Submit evidence requested by the Board to support his or her application.