What is the journal id of Anna Powierza?
SELECT T3.Journal_ID FROM journal_committee AS T1 JOIN editor AS T2 ON T1.Editor_ID   =   T2.Editor_ID JOIN journal AS T3 ON T1.Journal_ID   =   T3.Journal_ID WHERE T2.Name  =  "Anna Powierza"
journal id of Anna Powierza refers to JOIN operation between tables journal_committee, editor, and journal; filtering condition based on editor's name being Anna Powierza;