Del. Code tit. 15 § 7545
If only 1 qualified voter in the territory exists for the purpose of determining whether an annexation initiated pursuant to § 101A of Title 22 for the City of Wilmington shall be approved, notwithstanding any other provisions in this subchapter or in Title 22 the annexation shall be deemed approved if, within 7 days of the County Executive's approval of the county ordinance pursuant to § 101A(a)(2)f. of Title 22, the qualified voter files with the Clerk of the Peace a sworn affidavit approving of the annexation. If the qualified voter is a corporation, limited partnership or other entity, such affidavit must be accompanied by a suitable sealed, certified copy of a corporate resolution or its equivalent authorizing an officer, agent or other person to execute the affidavit approving the annexation on behalf of the entity. On receipt of said affidavit, together with the authorization, if any, the Clerk of the Peace shall certify the approval to the County Council and to the Wilmington City Council under that Clerk of the Peace's hand and seal. Said certification shall, for all intents and purposes, be construed as the required certificate under § 7544 of this title and § 101A(a)(2)f. of Title 22.
15 Del. C. § 7545