How to find if an application in the EBS system?

Dear All,

Could someone advise how to find if "General Ledger" or "Receivables" (applications or modules) in a client's EBS system or not?  

I am using below query that I can found if these are installed but do not know if they are in use.

  SELECT fat.application_id,
       FAT.APPLICATION_NAME,
       fdi.status,
       fdi.patch_level
FROM FND_APPLICATION_TL FAT, fnd_product_installations FDI
WHERE FDI.APPLICATION_ID = FAT.APPLICATION_ID AND fdi.status IN ('I', 'S')

Thanks in advance.
hbiuser