iBooks： The Swift Programming Language https://itunes.apple.com/jp/book/swift-programming-language/id881256329?mt=11 Using Swift with Cocoa and Objective-C https://itunes.apple.com/jp/book/using-swift-cocoa-objective/id888894773?mt=11
ドキュメント： The Swift Programming Language https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/ Using Swift with Cocoa and Objective-C https://developer.apple.com/library/content/documentation/Swift/Conceptual/BuildingCocoaApps/ Swift Standard Library https://developer.apple.com/reference/swift
