#56 Fix Twitter AuthenticationEndpoint

src/Microsoft.Owin.Security.Twitter/TwitterAuthenticationHandler.cs

@@ -22,7 +22,7 @@ namespace Microsoft.Owin.Security.Twitter
         private static readonly DateTime Epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
         private const string StateCookie = "__TwitterState";
         private const string RequestTokenEndpoint = "https://api.twitter.com/oauth/request_token";
-        private const string AuthenticationEndpoint = "https://twitter.com/oauth/authenticate?oauth_token=";
+        private const string AuthenticationEndpoint = "https://api.twitter.com/oauth/authenticate?oauth_token=";
         private const string AccessTokenEndpoint = "https://api.twitter.com/oauth/access_token";
 
         private readonly HttpClient _httpClient;