Business Object (BAPI/IDOC) for production Order

Hi All

I have requirement where data is coming from legacy system to R/3 via XI to generate a production order. I am not able to get right BAPI/ IDOC for inbound Production Order. Can anyone has done similar scenario. Can u suggest me BAPI or IDOC for same. I am using IS-Mills 4.7 version for R/3

Thanx in advance

Regards

Vinod