Question: What unit is in Mongolia?
SQL: SELECT "Unit" FROM "2-15313481-12" WHERE "Location" = 'Mongolia';

Question: What unit is in Argentina?
SQL: SELECT "Unit" FROM "2-15313481-12" WHERE "Location" = 'Argentina';

Question: What name is located in China?
SQL: SELECT "Name" FROM "2-15313481-12" WHERE "Location" = 'China';

Question: What unit is located in China and has Zhou Zhang as an author?
SQL: SELECT "Unit" FROM "2-15313481-12" WHERE "Location" = 'China' AND "Authors" = 'Zhou Zhang';