public Task<int> GetCountAsync(string surveyId, string samplingPointId)
{
CheckSurveyIdAndSamplingPointId(surveyId, samplingPointId);
var uri = $"{AddressesApi(surveyId, samplingPointId, null).AbsoluteUri}/Count";
return Client.GetAsync(uri)
.ContinueWith(rmt => int.Parse(rmt.Result.Content.ReadAsStringAsync().Result))
.FlattenExceptions();
}