Entity Framework double join code example

Example: Entity Framework double join

public class SomeContext: DbContext
    {
        public SometContext(DbContextOptions options) : base(options) { }

        public DbSet Relationships { get; set; }
        public DbSet Authors { get; set; }
        public DbSet Books { get; set; }


        public string GetTemplateMethods(string models)
        {
            var result = (from _relationships in Relationships
                join _books in Books on  equals 
                join _authors in Authors on _relationships.AuthorId equals _books.AuthorId

                select new
                {
                    AuthorName = _authors.MethodName,
                    AuthorId = _authors.AuthorId,
                    BookId = _books.BookId
                }).ToList();
            
            return JsonConvert.SerializeObject(result);
        }
    }