What are all institutions in "USA"?
select * from inst where country = "USA"
What papers did they publish?
select distinct t3.title from authorship as t2 join papers as t3 on t2.paperid = t3.paperid join inst as t4 on t2.instid = t4.instid where t4.country = "USA"
Among those, which have "Turon" as its second author?
select t3.title from authors as t1 join authorship as t2 on t1.authid = t2.authid join papers as t3 on t2.paperid = t3.paperid join inst as t4 on t2.instid = t4.instid where t4.country = "USA" and t2.authorder = 2 and t1.lname = "Turon"