What is this syntax: using "this" in property in C#?

Question

I happened to read this line of code:

public MyArray this [int index]{
    get{
        return array[index];
    }
}

Where can I find the document on msdn about the syntax of using "this" in property?

And is there any book covers this kind of tricky syntax of C# other than the common stuff?

Answer 1

It's an indexer.