Section 4(1)(b) in The Black Money (Undisclosed Foreign Income And Assets) And Imposition Of Tax Act, 2015
(b)the income, from a source located outside India, in respect of which a return is required to be furnished under section 139 of the Income-tax Act but no return of income has been furnished within the time specified in Explanation 2 to sub-section (1) or under sub-section (4) or sub-section (5) of section 139 of the said Act; and