I.: Peterson, Roger Tory; Chalif, Edward L.: A Field Guide to Mexican Birds. Field Marks of all Species found in Mexico, Guatemale, Belize, El Salvator. Boston, Houghton Mifflin 1973. cloth w. dust jacket. ISBN 0395171296 / II.: Davis, Irby L.: A Field Guide to the Birds of Mexico and Central America. Austin, Univ, of Texas Press 1972. Pbk. ISBN 0292707029 / III.: Raffaele, Herbert A.: A Guide to the Birds of Puerto Rico and the Virgin Islands. Revised Edition. Priceton, Princeton Univ. Press 1989. Pbk. ISBN 0691024243 / IV.. Snow, David W.: The Web of Adaptation. Bird Studies in the American Tropics. London, Collins 1976. cloth w. dust jacket. ISBN 0002197359 / V.: Meyer de Schauensee, Rodolphe; Phelps, William H.: A Guide to the Birds of Venezuela. Priceton, Princeton Univ. Press 1978. Pbk. All books in fair condition.