2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/151038This paper presents a unified approach to parsing, in which top-down, bottom-up and left-corner parsers are related to preorder, postorder and inorder tree traversals. It is shown that the simplest bottom-up and left-corner parsers are left recursive and must be converted using an extended Greibach normal form. With further partial execution, the bottom-up and left-corner parsers collapse together as in the BUP parser of Matsumoto.COLING 94 paper, Postscript, compressed and uuencodedComputation and Languagetext