CREATE TABLE table_204_597 (id NUMBER, "main author" CLOB, "no. of patients" NUMBER, "duration of follow-up years" NUMBER, "linearized rate of infection" CLOB, "actuarial freedom from infective endocarditis" CLOB)

what is the minimum of follow up years do each author have ?
SELECT MIN("duration of follow-up years") FROM table_204_597
SELECT MIN("duration of follow-up years") FROM "table_204_597"