CREATE TABLE submission (Author VARCHAR(255), Submission_ID VARCHAR(255)); CREATE TABLE acceptance (Submission_ID VARCHAR(255), workshop_id VARCHAR(255))
Show the authors who have submissions to more than one workshop.
    
SQL: SELECT T2.Author FROM acceptance AS T1 JOIN submission AS T2 ON T1.Submission_ID = T2.Submission_ID GROUP BY T2.Author HAVING COUNT(DISTINCT T1.workshop_id) > 1