Books designed by the arrangement and treatment of their subject matter to be consulted for definite terms of information rather than to be read consecutively. Reference books include DICTIONARIES; ENCYCLOPEDIAS; ATLASES; etc. (From the ALA Glossary of Library and Information Science, 1983)
Works about instruction in which learners progress at their own rate using workbooks, textbooks, or electromechanical devices that provide information in discrete steps, test learning at each step, and provide immediate feedback about achievement. (ERIC, Thesaurus of ERIC Descriptors, 1996).