Dilley, Clyde A. Lowry, David W. Ockenga, Earl C. text Lexington D.C. Heath and Company c1985 monographic 474 p. : col. ill. ; 24 cm. Walter E. Rucker, Clyde A. Dilley [and] David W. Lowry ; contributing author : Earl C. Ockenga. Includes glossary and index. Arithmetic 513 R911 1985 0669074217