Call webservice from sharepoint 2013 worflow

https://msdn.microsoft.com/en-us/library/fp142385.aspx

https://msdn.microsoft.com/en-us/library/office/dn567558.aspx

https://sergeluca.wordpress.com/2013/04/09/calling-the-sharepoint-2013-rest-api-from-a-sharepoint-designer-workflow/

https://msdn.microsoft.com/en-us/library/office/dn567558.aspx

http://blogs.msdn.com/b/thirusrinivasan1/archive/2013/10/31/sharepoint-2013-workflow-calling-a-wcf-service.aspx