using AIF, cannot locate Amount in VendVendInvoiceService

HI,

   I have a business requirement to get Purchase Order from AX using PurchPurchRequestService and push the following information ( Vendor Invoice ) using VendVendInvoiceService into AX. Unfortunately there is no field matching "amount" in VendVendInvoiceService i have seen all the inner objects and collections by running debugger and quick watch in visual studio. Please Help.

AxdVendInvoice objAxdVendInvoice = new AxdVendInvoice();

AxdEntity_VendInvoiceInfoTable[] axdEntity_VendInvoiceInfoTable = new AxdEntity_VendInvoiceInfoTable[0];

AxdEntity_VendInvoiceInfoSubTable[] axdEntity_VendInvoiceInfoSubTable = new AxdEntity_VendInvoiceInfoSubTable[0];

AxdEntity_VendInvoiceInfoLine[]  axdEntity_VendInvoiceInfoLine = new AxdEntity_VendInvoiceInfoLine[0];

AxdEntity_VendInvoiceInfoLine_Project[] axdEntity_VendInvoiceInfoLine_Project =  new AxdEntity_VendInvoiceInfoLine_Project[0];

axdEntity_VendInvoiceInfoTable[0].???Amount

question mark indicates missing field ( amount ). Is there any field that can give me invoice amount?