What are the issue dates of volumes associated with the artist "Gorgoroth"?
create table artist (artist_id varchar, artist varchar, PRIMARY KEY (artist_id)); create table volume (issue_date varchar, artist_id varchar, PRIMARY KEY (issue_date))
select t2.issue_date from artist as t1 join volume as t2 on t1.artist_id = t2.artist_id where t1.artist = "gorgoroth"