BooksConsolapp/Books.ConsoleApp/BooksByAuthor.cs

using System.Collections.Generic;

namespace Books.ConsoleApp
{
    public class BooksByAuthor
    {
        public readonly string Author;
        public readonly List<Book> Books;

        public BooksByAuthor(string author, List<Book> books)
        {
            Author = author;
            Books = books;
        }
    }
}