user: Question: What is the paper type that the one that was issued on 26 July 2007 done on?
Columns: ['Date of Issue', 'Denomination', 'Design', 'Paper Type', 'First Day Cover Cancellation']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['5 January 2007', '52 cents', 'John Belisle, Kosta Tsetsekas', 'Tullis Russell Coatings', 'Toronto, ON']
SQL:

assistant: SELECT "Paper Type" FROM "Table" WHERE "Date of Issue" = '26 July 2007';