CREATE TABLE table_72440 ("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 the episode that received 1.83 million U.S. viewers?
SELECT "Written by" FROM table_72440 WHERE "U.S. viewers (millions)" = '1.83'
SELECT "Written by" FROM "table_72440" WHERE "U.S. viewers (millions)" = '1.83'