(This is the Scala textbook that has been translated and published in G. As long as more than 200 pages, it is a good book to get started. The translation is called "Scala Programming: Java Virtual Machine Multi-Core Programming Practice" (the first Scala book in G), but my book is a complete e-book in English, even better!
"ProgrammingScala" (pencil book 2009-7).pdf)