This video, https://www.youtube.com/watch?v=QDCXhR65SxY&index=4&list=PLSjtLzqIlLSUeIS1X8tsYVxqL0qfH62fn, can also be seen at https://www.youtube.com/playlist?list=PLSjtLzqIlLSUeIS1X8tsYVxqL0qfH62fn.