public ContactInformation ChangeSecondaryTelephone(Telephone telephone)
 {
     return(new ContactInformation(
                this.EmailAddress,
                this.PostalAddress,
                this.PrimaryTelephone,
                telephone));
 }
 public ContactInformation(
     EmailAddress emailAddress,
     PostalAddress postalAddress,
     Telephone primaryTelephone,
     Telephone secondaryTelephone)
 {
     this.EmailAddress       = emailAddress;
     this.PostalAddress      = postalAddress;
     this.PrimaryTelephone   = primaryTelephone;
     this.SecondaryTelephone = secondaryTelephone;
 }
 public Telephone(Telephone telephone)
     : this(telephone.Number)
 {
 }