Updated post as I just found out that you can read the full text by using Amazon "Inside This Book" search function. Just search for the key word Daney and turn the pages (from 68 to 79).
This is an essential text by Gilles Deleuze on Serge Daney:
"Letter to Serge Daney: Optimism, Pessimism, and Travel", Negotiations 1972-1990, New York: Columbia University Press, 1995, translated by Martin Joughin, pp.68-79.
Original text is Deleuze's preface to "Optimisme, pessimisme et voyage: Lettre à Serge Daney" for Serge Daney, Ciné journal 1981-1986, Cahiers du cinéma, 1986.