CREATE TABLE inst (country VARCHAR(255), instid VARCHAR(255)); CREATE TABLE authorship (instid VARCHAR(255), paperid VARCHAR(255)); CREATE TABLE papers (paperid VARCHAR(255))
Retrieve the country that has published the most papers.
    
SQL: SELECT t1.country FROM inst AS t1 JOIN authorship AS t2 ON t1.instid = t2.instid JOIN papers AS t3 ON t2.paperid = t3.paperid GROUP BY t1.country ORDER BY COUNT(*) DESC LIMIT 1