Reference Material in the form of subject dictionaries, encyclopedias, and handbooks typically provide background essays, definitions, broad overviews of various topics, or other pertinent facts:
Oxford Bibliographies: Social Work
DSM-5 & DSM Legacy Library includes: DSM-5 Diagnostic and Statistical Manual of Mental Disorders, 5th Edition -- DSM-5 Handbook of Differential Diagnosis -- DSM-5 Clincal Cases -- DSM-IV-TR: Diagnostic and Statistical Manual of Mental Disorders, 4th Edition -- DSM-IV: Diagnostic and Statistical Manual of Mental Disorders, 4th Edition -- DSM-III-R: Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition Revised -- DSM-III: Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition -- DSM-II 6th printing change: Elimination of Homosexuality as a mental disorder and substitution of the new category Sexual Orientation Disturbance -- DSM-II: Diagnostic and Statistical Manual of Mental Disorders, 2nd Edition -- DSM-I Special Supplement: on plans for revision to better align with the International Classification of Diseases -- DSM-I: Diagnostic and Statistical Manual: Mental Disorders.