CREATE TABLE table_16783 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" CLOB, "Directed by" CLOB, "Written by" CLOB, "Original air date" CLOB, "U.S. viewers  ( millions ) " CLOB)

Who wrote an episode watched by 19.01 million US viewers?
SELECT "Written by" FROM table_16783 WHERE "U.S. viewers (millions)" = '19.01'
SELECT "Written by" FROM "table_16783" WHERE "U.S. viewers (millions)" = '19.01'