An appeal consists of a timely filed Notice of Disagreement submitted in accordance with the provisions of § 19.21 , and either § 19.52(a) or § 20.501(a) of this chapter, as applicable and, after a Statement of the Case has been furnished, a timely filed Substantive Appeal.
38 C.F.R. §19.20
Authority: 38 U.S.C. 7105 (2016)