SOAP API: Custom Object parent of Incident

Content

Hi all, 

I have a custom object (called Poliza) set up as a parent of Incident. 

In Incident I have a CO.id_poliza for relationship, also, I have some Custom Fields in Incident.

I am saving at Incident's fields, Incident's Custom Fields excepts Incident's Custom Object.

How I can save a relation field into Incident (CO.id_poliza)?

 

 

 

 

Version

August 2015