A Regular Expression to validate alphabetic characters with dots and spaces in C#

Suppose we have a string like A.K. Ramaswamy

And we want to write the regular expression for the same. The below will do so

using System;
using System.Text.RegularExpressions;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            var input = "A.K. Ramaswamy";           
            Regex rgx = new Regex(@"^[a-zA-Z. ]*$");
            Console.WriteLine(rgx.IsMatch(input));
            Console.ReadKey();
        }
    }
}