Delaware Code
Subchapter I. General Provisions
§ 701. Creation of estate in joint tenancy; exception.

No estate, in joint tenancy, in lands, tenements or hereditaments shall be held or claimed by or under any grant, devise or conveyance made to any persons, other than to executors or trustees, unless the premises therein mentioned are expressly granted, devised or conveyed to such persons, to be held as joint tenants and not as tenants in common.