Avoidance of Double Taxation secured for freight earnings of Czechoslovak vessels, exempt from Indian income tax by reciprocity. Article 12 exempts freight earnings of Czechoslovak vessels from Indian income tax on the basis of reciprocity; the Central Government, invoking section 90 of the Income tax Act, 1961 and section 24A of the Companies (Profits) Surtax Act, 1964, directed that Article 12 be given effect in India by notification dated 3 June 1980, within a broader bilateral shipping agreement that also defines vessel and crew terms, recognises ship documents, provides port facilities and assistance, and sets cargo sharing and coordination mechanisms.