Taxes Covered define taxable categories and require mutual notification of significant tax-law changes and inclusion of similar taxes adopted later. Article 2 enumerates the domestic taxes covered by the treaty-India: income-tax (including surcharges) and companies' surtax; Czechoslovakia: taxes on profits, wages tax, income from literary and artistic activities, agricultural tax, population income tax and house tax-and makes the agreement applicable to any identical or substantially similar taxes introduced later. It also requires the competent authorities to notify each other annually of significant legislative changes affecting the covered taxes and to exchange copies of relevant enactments and regulations.