Double taxation relief: agreements permit relief, information exchange and recovery, with domestic law applying if more beneficial. The Central Government may enter into agreements to provide double taxation relief, avoid double taxation, exchange information to prevent evasion or avoidance, and recover tax, and may notify implementing provisions. Treaty-applicable assessees receive the benefit of domestic provisions to the extent more beneficial, subject to Chapter X-A applying regardless. Non-residents claiming treaty relief must obtain a certificate of residence and furnish prescribed documents. Undefined terms are given meanings by Central Government notification unless inconsistent with the Act or the agreement.