English 2600 : a programed course in grammar and usage / Joseph C. Blumenthal. - 5th ed. with index. - N.Y. [et al.] : HBJ, [1981]. - xxi, 448 p. ; 23 cm.см.. - (The College series). - With: Blumenthal, Joseph C. "Answer key for tests for English, 2600".- 7 p.- 1981. - ISBN 0-15-522716-5; ISBN 0-15-5227m18-1 (Answer key)[MFN: 22899]