The works

Along the top and bottom rows of the grid runs a seasonal quotation of 11 words. 81 clues contain a superfluous word; the initial letters of these words in clue order spell out another seasonal quotation of 21 words; ignore the apostrophe. Other unclued lights (five of two words, one of three), singly or linked, give the surnames of the two authors, the works from which the quotations come, and titles of six other works by each author.