Create a custom relation in a custom bol to return entity of Type ERPOrder

Hi Experts,

I want to create a custom relation on a result object of a custom BOL to return an entity

of type 'ERPOrder'.I could not find any information on this on the internet on how do we code for BOL

relations to return data, how are the genil classes configured for it etc.Please can anyone guide.

Kind Regards,

Ankit