Who wrote an episode watched by 19.01 million US viewers?
CREATE TABLE "table1_11411026_2" (
  "no_in_series" real,
  "no_in_season" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text,
  "u_s_viewers_millions" text
);
SELECT "written_by" FROM "table1_11411026_2" WHERE "u_s_viewers_millions"='19.01';