Reference Number on Shipping Label?

[rmhachar]

Hello everybody!

I'm a long-time ebay seller and one of my customers, as part of the global shipping program, has an address with a reference number listed. I've never actually had a customer with one of these numbers and am confused as to whether or not I should include it on the shipping label. 

The address of my customer is as follows (information has been removed to protect the buyers identity):

Name

Reference#OREUSA##########CA

Address

State, City, Zip

United States

So the question is: should I include the reference number on the envelope?

Thank you so much for your help! It's greatly appreciated!