sql injection:
http://www.puritys.me/filemanage/blog_files/advance_sql_injection.pdf
http://www.jb51.net/article/31898.htm
http://w1a2d3s4q5e6.blogspot.tw/2013/06/php.html
php book:
http://issuu.com/milesgelidus/docs/johnwileysons-php5fordummies
http://issuu.com/abdulfazil/docs/php-object-oriented-solutions.9781430210115.35911
html5:
http://issuu.com/tavotribilin/docs/oreilly.html5.the.missing.manual.au
duolingo:
https://www.duolingo.com/
css style:
http://www.shejidaren.com/css-button-generator-and-beautifucl-style-sheet.html
