user: Question: If the region is the Southern District of Texas, what is the citation?
Columns: ['Region', 'Citation', 'Court of Appeals', 'Established', 'Judges', 'Meeting places', 'Chief judge']
Types: ['text', 'text', 'text', 'real', 'real', 'real', 'text']
Sample row: ['Northern District of Alabama', 'N.D. Ala.', '11th', 1820.0, 8.0, 8.0, 'Sharon Lovelace Blackburn']
SQL:

assistant: SELECT "Citation" FROM "Table" WHERE "Region" = 'Southern District of Texas';