CREATE TABLE table_20516 ("RR Romaja" TEXT, "M\\u2013R Romaja" TEXT, "Hangul/Chosongul" TEXT, "Hanja" TEXT, "ISO" TEXT, "Area" TEXT, "Capital" TEXT, "Region" TEXT, "Country" TEXT)

Name the iso for chungcheongnam
SELECT "ISO" FROM table_20516 WHERE "RR Romaja" = 'Chungcheongnam'
SELECT "ISO" FROM "table_20516" WHERE "RR Romaja" = 'Chungcheongnam'