R011.02 Sho E Shores, Louis. Basic reference books. An introduction to the evaluation, study and use of reference materials with special emphsis on some 300 title, by Louis Shores, 2. ed. Chicago, Ill., American Library Association, 1939. xiii, 472 p. tablas. 24 cm. ´´Apendix I. Core collection: alphabetical checkelist´´: p. (415)-446