*[The Swift Programming Language](https://itunes.apple.com/us/book/swift-programming-language/id881256329?mt=11)(iBook)
*[The Swift Programming Language](https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/index.html)(HTML)
*[Using Swift with Cocoa and Objective-C](https://itunes.apple.com/us/book/using-swift-cocoa-objective/id888894773?mt=11)(iBook)