Tecnica de la eleccion vocacional :

BIBTEX Dublin Core MARCXML MARC (non-Unicode/MARC-8) MARC (Unicode/UTF-8) MARC (Unicode/UTF-8, Standard) MODS (XML) RIS ISBD

Other Libraries (WorldCat) Other Databases (Google Scholar) Online Stores (Bookfinder.com) Open Library (openlibrary.org)