S. 40(a)(ia): Amounts not deductible-Deduction at source-Short deduction of tax at source-Merely a short deduction of TDS by assessee under section 194C, and persons to whom payments were made by assessee had paid taxes on such payments, Assessing Officer could not have invoked provisions of section 40(a)(ia) and disallowed expenses claimed by assessee-Order of Tribunal affirmed. [S. 194C; Second proviso, 194I, 260A]