?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aulast=Pettorossi&rft.au=Pettorossi%2C+Alberto&rft.aufirst=Alberto&rft.btitle=A+25-Year+Perspective+on+Logic+Programming%3A+Achievements+of+the+Italian+Association+for+Logic+Programming%2C+GULP&rft.title=The+Transformational+Approach+to+Program+Development&rft.isbn=978-3-642-14308-3&rft.date=2010&rft.genre=bookitem