private IEnumerable<DocumentItem> GetDocumentItems(string documentNumber)
{
var function = Operation.DocumentItems;
var options = new Dictionary<string, string> { { "doc_number", documentNumber } };
var url = GetUrl(function, options);
var docItemsXml = RepositoryUtils.GetXmlFromStream(url);
function = Operation.CircStatus;
options = new Dictionary<string, string> { { "sys_no", documentNumber } };
url = GetUrl(function, options);
var docCircItemXml = RepositoryUtils.GetXmlFromStream(url);
return DocumentItem.GetDocumentItemsFromXml(docItemsXml.ToString(), docCircItemXml.ToString(), _rulesRepository);
}