. . . "Interstate apportionment of business income for State income tax purposes with specific reference to North Carolina"@en . . "Interstate apportionment of business income for state income tax purposes : with specific reference to North Carolina"@en . . "Interstate apportionment of business income for State income tax purposes : with specific reference to North Carolina"@en . "Interstate apportionment of business income for State income tax purposes : with specific reference to North Carolina" . . . . . . . . . . . . .