///////////////SO//////////////////////

            var salesOrder = altumServices.SalesOrderService.CreateEmptyDocument();
            salesOrder.ForeignNumber = "ReferenceIR1";

            List<SpendingElement> elements = new List<SpendingElement>();

            var createParams1 = new CreateEmptyElementsParameters(salesOrder, article1.Id, 0);
            var element1 = altumServices.SalesOrderService.CreateEmptyElements(createParams1).FirstElementResult;
            element1.Quantity = 1;
            element1.Value = 10;
            element1.Number = 1;
            elements.Add(element1);

            var createParams2 = new CreateEmptyElementsParameters(salesOrder, article2.Id, 0);
            var element2 = altumServices.SalesOrderService.CreateEmptyElements(createParams2).FirstElementResult;
            element2.Quantity = 2;
            element2.Value = 20;
            element2.Number = 2;
            elements.Add(element2);

            //var updateParams2 = new UpdateSpendingElementsParameters(salesOrder, elements);
            //altumServices.SalesOrderService.UpdateElements(updateParams2);

            var createParams3 = new CreateEmptyElementsParameters(salesOrder, article3.Id, 0);
            var element3 = altumServices.SalesOrderService.CreateEmptyElements(createParams3).FirstElementResult;
            element3.Quantity = 3;
            element3.Value = 30;
            element3.Number = 3;
            elements.Add(element3);

            var createParams4 = new CreateEmptyElementsParameters(salesOrder, article4.Id, 0);
            var element4 = altumServices.SalesOrderService.CreateEmptyElements(createParams4).FirstElementResult;
            element4.Quantity = 4;
            element4.Value = 40;
            element4.Number = 4;
            elements.Add(element4);

            var updateParams1 = new UpdateSpendingElementsParameters(salesOrder, elements);
            altumServices.SalesOrderService.UpdateElements(updateParams1);

            altumServices.SalesOrderService.SaveAndAccept(salesOrder);

            var numbers = salesOrder.Elements.Select(e => e.OrdinalNumber);
            #endregion


            //Checking PO

            BEExpression refExpression1 = new BEValueExpression(InvoiceRowDataProperties.SourceNumber, ValueOperator.Equals, "ReferenceIR1");

            var soDocument = altumServices.SalesOrderService.GetSalesOrdersList(new BEFilter(refExpression1)).First();

            var numbers2 = soDocument.Elements.Select(e => e.OrdinalNumber);



////////////////////////

        public static void CreateExampleArticle(IStandardAltumServices altumServices, string articleCode)
        {
            if (altumServices.ArticleService.ExistArticle(articleCode))
            {
                return;
            }

            var article = altumServices.ArticleService.GetEmptyArticle();
            article.Code = articleCode;
            article.Name = articleCode;
            article.Active = true;

            altumServices.ArticleService.SaveArticle(article);
        }