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Pushdown automaton - http://en.wikipedia.org/wiki/Pushdown_automaton
A Wikipedia article with a definition and simple example. |
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Non-determinsitic Pushdown Automata - http://users.comlab.ox.ac.uk/luke.ong/teaching/moc/pda2up.pdf#search=%22pushdown%20automata%22
A definition of NPDA with examples and a proof that NPDA accept context free languages. |
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Push-Down Automata - http://web.uvic.ca/~ling48x/ling484/notes/pda.html
Notes for a linguistics course defining PDA and showing their relation to context free languages. |
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Pushdown Automata - http://www.cs.nott.ac.uk/~txa/g51mal.2001/notes/node29.html
A site with a formal definition of PDA, some examples and a proof that PDA accept context free languages. |
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Pushdown Automata and Context Free Languages - http://homepages.fh-regensburg.de/~zar39030/in/node6.html
An article with basic definitions and a proof that the languages accepted by PDA are context free languages. |