CREATE TABLE table_204_843 (id DECIMAL, "volume" DECIMAL, "year" TEXT, "names" TEXT, "articles" DECIMAL, "pages" DECIMAL, "images" DECIMAL, "maps" DECIMAL, "number of copies" DECIMAL)

how many articles were published in the 6th volume ?
SELECT "articles" FROM table_204_843 WHERE "volume" = 6
SELECT "articles" FROM "table_204_843" WHERE "volume" = 6