Can someone help me generate the Interface (c#) file for the following OGC schema?

Schema files: Download Schema Files Link

I need to create web services for the Ordering wsdl in the schema zip file above. I've been at it for days now with no luck generating the interface. I've tried:

svcutil.exe thewsdl.wsdl /language:c# /out:ITheInterface.cs

svcutil Order.wsdl /out:IOrder.cs

svcutil Order.wsdl Order.xsd ..\ws-addressing\ws-addr.xsd /out:IOrder.cs

svcutil Order.wsdl Order.xsd ws-addr.xsd /out:IOrder.cs

and i get the following error:

Microsoft (R) Service Model Metadata Tool
[Microsoft (R) Windows (R) Communication Foundation, Version 4.0.30319.1]
Copyright (c) Microsoft Corporation.  All rights reserved.

Error: Cannot read ws-addr.xsd.

    Cannot load file D:\Documents\DEV\SARPilot\Docs\eoschema\schema\OrderSchema\ws-addr.xsd as an Assembly. Check the FusionLogs f
or more Information.

    Could not load file or assembly 'file:///D:\Documents\DEV\SARPilot\Docs\eoschema\schema\OrderSchema\ws-addr.xsd' or one of its
 dependencies. The module was expected to contain an assembly manifest.