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I have created this book from PHP Language Spec github repo, so basically its not mine, nor I have wrote any word inside of it.
But the main Question, why did I created this book, why i didnt just use the repo, well to be honest am a lazy person, and I found it hard to read books and documentations from github, especially that I set too much behind my screens ( and yes they are old 19" model ) so the brightness and the resolution is not something I like, but I have to deal with, so I had this idea of why not to convert it to epub, and I though that many people might find it useful, so I just created and put the markup files which they have, and the result was a free book which you can get from leanpub at "PHP Language Specifications"
but after I designed the small cover, and created the book I noticed that the markup files need some fixing to work with leanpub, so I will be working on those from time to time based on my free time.
Just wish me luck.