reference work
reference work1
(n.) = obra de referencia, obra de consulta.
Ex: A university library, for example, might group its holdings into 'no loans allowed' for important reference works.
reference work2
(n.) = trabajo de referencia.
Ex: But librarianship is a multi-disciplinary study, and reference work, though squarely based on systematic bibliography, owes more than most aspects of librarianship to other disciplines.