select distinct substring(name,1,1) from stamps ,np_master where year(stamps.issue_date)=1956 and month(issue_date)=5 and np_master.np_code=stamps.np_code and np_master.np='A' and stamps.serial_no='0373' order by substring(name,1,1)
IndianPost
Issue Date >> year >> 1956 >> month >> May >> Currency >> A >> Serial Number >> 0373 >> Alpha >> R >>