user: Question: In what poll is Nathan Deal at 13% and John Oxendine at 28%?
Columns: ['Poll source', 'Dates administered', 'John Oxendine', 'Karen Handel', 'Nathan Deal', 'Eric Johnson', 'Ray McBerry', 'Undecided']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Magellan Strategies', 'July 18, 2010', '12%', '38%', '20%', '17%', '3%', '7%']
SQL:

assistant: SELECT "Poll source" FROM "Table" WHERE "Nathan Deal" = '13%' AND "John Oxendine" = '28%';