Question: Find the name of the scientist who worked on both a project named 'A Matter of Time' and a project named 'A Puzzling Parallax'.
SQL: SELECT T3.name FROM assignedto AS T1 JOIN projects AS T2 ON T1.project  =  T2.code JOIN scientists AS T3 ON T1.scientist  =  T3.SSN WHERE T2.name  =  'Matter of Time' INTERSECT SELECT T3.name FROM assignedto AS T1 JOIN projects AS T2 ON T1.project  =  T2.code JOIN scientists AS T3 ON T1.scientist  =  T3.SSN WHERE T2.name  =  'A Puzzling Parallax'