Can't find Microsoft.IdentityModel.dll and System.ServiceModel.dll

Hey Guys:

  I use the Simple STS example from the msdn. Example is below:

using System;
using System.ServiceModel;

using Microsoft.IdentityModel.Claims;
using Microsoft.IdentityModel.Configuration;
using Microsoft.IdentityModel.Protocols.WSTrust;
using Microsoft.IdentityModel.SecurityTokenService;

namespace ClaimsAwareWebService
{
    public class MySecurityTokenService : SecurityTokenService
    {
        const string addressExpected = "http://localhost:6020/ClaimsAwareWebService";
        const string encryptingCertificateName = "CN=localhost";

        /// <summary>
        /// Creates an instance of the MySecurityTokenService class.
        /// </summary>
        /// <param name="configuration">SecurityTokenServiceConfiguration element.</param>

        public MySecurityTokenService(SecurityTokenServiceConfiguration configuration)
            : base(configuration)
        {
        }

        /// <summary>
        /// This method returns the configuration for the token issuance request. The configuration
        /// is represented by the Scope class. In our case, we are only capable of issuing a token to a
        /// single RP identity represented by CN=localhost.
        /// </summary>
        /// <param name="principal">The caller's principal</param>
        /// <param name="request">The incoming RST</param>
        /// <returns>The configuration for the token issuance request.</returns>
        protected override Scope GetScope(IClaimsPrincipal principal, RequestSecurityToken request)
        {
            // Validate the AppliesTo on the incoming request
            ValidateAppliesTo(request.AppliesTo);

            // Normally the STS will have a trust relationship with the RP and can look up a trusted encrypting certficate
            // using the AppliesTo endpoint. This is necessary to ensure that only the RP will be able to read the claims.
            //
            // In this sample the certificate of the AppliesTo Identity is used to encrypt the contents, so there is no
            // validation of any trust relationship with the RP. Since the certificate is not validated,
            // a malicious client can provide a known certificate allowing it to read the returned claims.
            // For this reason, THIS APPROACH SHOULD NOT BE USED if the claims should be kept private. It may be reasonable,
            // though, if the STS is simply verifying public information such as the client's email address.

            // Get RP certificate
            X509CertificateEndpointIdentity appliesToIdentity = (X509CertificateEndpointIdentity)request.AppliesTo.Identity;

            X509EncryptingCredentials encryptingCredentials = new X509EncryptingCredentials(appliesToIdentity.Certificates[0]);
            // Create the scope using the request AppliesTo address and the STS signing certificate
            Scope scope = new Scope(request.AppliesTo.Uri.AbsoluteUri, SecurityTokenServiceConfiguration.SigningCredentials, encryptingCredentials);
            return scope;
        }

        /// <summary>
        /// Validates the appliesTo and throws an exception if the appliesTo is null or appliesTo contains some unexpected address.
        /// </summary>
        void ValidateAppliesTo(EndpointAddress appliesTo)
        {
            if (appliesTo == null)
            {
                throw new InvalidRequestException("The appliesTo is null.");
            }

            if (!appliesTo.Uri.Equals(new Uri(addressExpected)))
            {
                Console.WriteLine("The relying party address is not valid. ");
                throw new InvalidRequestException(String.Format("The relying party address is not valid. Expected value is {0}, the actual value is {1}.", addressExpected, appliesTo.Uri.AbsoluteUri));
            }
        }


        /// <summary>
        /// This method returns the claims to be included in the issued token.
        /// </summary>
        /// <param name="scope">The scope that was previously returned by GetScope method</param>
        /// <param name="principal">The caller's principal</param>
        /// <param name="request">The incoming RST</param>
        /// <returns>The claims to be included in the issued token.</returns>
        protected override IClaimsIdentity GetOutputClaimsIdentity(IClaimsPrincipal principal, RequestSecurityToken request, Scope scope)
        {


            if (null == principal)
            {
                throw new InvalidRequestException("The caller's principal is null.");
            }



            // Get the incoming IClaimsIdentity from IPrincipal
            IClaimsIdentity callerIdentity = (IClaimsIdentity)principal.Identity;


            // Create the output IClaimsIdentity
            IClaimsIdentity outputIdentity = new ClaimsIdentity();

            // Create a name claim from the incoming identity.
            Claim nameClaim = new Claim(ClaimTypes.Name, callerIdentity.Name);

            // Create an 'Age' claim with a value of 25. In a real scenario, this may likely be looked up from a database.
            Claim ageClaim = new Claim("http://WindowsIdentityFoundationSamples/2008/05/AgeClaim", "25", ClaimValueTypes.Integer);

            // Add the name
            outputIdentity.Claims.Add(nameClaim);
            outputIdentity.Claims.Add(ageClaim);

            return outputIdentity;
        }


    }
}

But, It can't find System.ServiceModel.dll and Microsoft.IdentityModel.dll. My .net Version is 4.5.  I have looked for those dll all around the directory C:. But I failed. I want to know where can I get those dll and why .net 4.5 is not include those dll. Thank you for your answers.