The Collaborative International Dictionary of English v.0.48:

casebook \case"book`\ n.
   a book in which detailed written records of cases are kept
   and which are a source of information for subsequent work.
   Such books are often used as supplements to texts in law
   schools.
   [WordNet 1.5 +PJC]

WordNet (r) 3.0 (2006):

casebook
    adj 1: according to or characteristic of a casebook or textbook;
           typical; "a casebook schizophrenic"; "a textbook example"
           [syn: casebook, textbook]
    n 1: a book in which detailed written records of a case are kept
         and which are a source of information for subsequent work