Database: aan_1
Question: What are the names of authors who published in both NAACL and ACL in 2009?
SQL:
SELECT name FROM Author WHERE author_id IN (SELECT T1.author_id FROM Author_list AS T1 JOIN Paper AS T2 ON T1.paper_id  =  T2.paper_id WHERE T2.venue  =  "ACL" AND T2.year  =  2009 INTERSECT SELECT T1.author_id FROM Author_list AS T1 JOIN Paper AS T2 ON T1.paper_id  =  T2.paper_id WHERE T2.venue  =  "NAACL" AND T2.year  =  2009)