of the document being referenced, nor any reasonable doubt about the fact that the referenced document is being incorporated into the contract.’ ” Lakeshore Eng’g Servs., Inc. v. United States, 748 F.3d at 1347 (quoting Northrop Grumman Info. Tech., Inc. v. United States, 535 F.3d 1339, 1344 (Fed. Cir. 2008)). Because an ambiguous or uncertain writing sometimes only can be understood upon consideration of the surrounding circumstances, courts may rely on extrinsic evidence to interpret an ambiguous contract clause. See Cruz-Martinez v. Dep’t of Homeland Sec., 410 F.3d 1366, 1371 (Fed. Cir. 2005) (“ ‘Meaning can almost never be plain except in a context.’ ” (quoting Restatement (Second) of Contracts § 212, cmt. b (1981))); Barron Bancshares, Inc. v. United States, 366 F.3d at 1375 (<HOLDING>); Sylvania Elec. Prods., Inc. v. United States,
holding that court may not use extrinsic evidence unless contract language is ambiguous holding that extrinsic evidence is permissible to interpret an ambiguous contract holding extrinsic evidence may be used only to interpret not alter a written contract holding that a court may consider extrinsic evidence to determine whether a contract is ambiguous holding that extrinsic evidence of the parties course of conduct may be considered where the contract language is ambiguous