//Gets the value of the global property
        Integer identifierId = Integer
                .parseInt(Context.getAdministrationService().getGlobalProperty("global property name"));
        //Gets the patient
        Patient patient = Context.getPatientService().getPatient(patientId);//Edit this patientId
        //Gets the Parpar identifier
        PatientIdentifier identifier = patient.getPatientIdentifier(identifierId);
        //Checkes Whether this patient really has that identifier
        if (identifier != null) {
            String thisIsWhatYouNeed = identifier.getIdentifier();//Change this variable name and concatinate this to the href string
        } else {
            //do something (like - don't add the link)
        }