Method of accounting: permits cash or mercantile systems and allows assessment where accounting or disclosure standards are not followed. Method of accounting for income under the heads Profits and gains of business or profession and Income from other sources permits either cash or mercantile systems if regularly employed; the Central Government may notify income computation and disclosure standards for classes of assessees or income, and the Assessing Officer may make an assessment where accounts are incorrect or incomplete, the accounting method has not been regularly followed, or income is not computed as per notified standards.