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README.md

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 ### Tutorial
-- The most up-to-date examples are in app/{parser,ambiguous,error,syntaxcompletion}.
-- [How to write and run a parser](https://github.com/kwanghoon/yapb/blob/master/doc/Tutorial-parser.md)
-- [How to write and run a syntax completion server for Emacs](https://github.com/kwanghoon/yapb/blob/master/doc/Tutorial-syntax-completion.md)
-- [For AST and interpreter: A top-down approach to writing a compiler for arithmetic expressions](https://github.com/kwanghoon/swlab_parser_builder/blob/master/doc/tutorial_swlab_parser_builder.txt) Written in Korean.
+- As a tutorial, the most up-to-date examples are available in app/{parser,ambiguous,error,syntaxcompletion}.
 - [For parser: Parser generators sharing LR automaton generators and accepting general purpose programming language-based specifications](http://swlab.jnu.ac.kr/paper/kiise202001.pdf) Written in Korean.
 - [For syntax complection with YAPB-0.1.2:  A text-based syntax completion method using LR parsing (PEPM 2021)](http://swlab.jnu.ac.kr/paper/pepm2021final.pdf).