CREATE TABLE table_39801 ("Name" CLOB, "Status" CLOB, "Authors" CLOB, "Unit" CLOB, "Location" CLOB, "Notes" CLOB)

What unit is located in China and has Zhou Zhang as an author?
SELECT "Unit" FROM table_39801 WHERE "Location" = 'china' AND "Authors" = 'zhou zhang'
SELECT "Unit" FROM "table_39801" WHERE "Authors" = 'zhou zhang' AND "Location" = 'china'