S. 69 :Unexplained investments-Survey-Cash and stock-Excess stock offered as business income-Deeming provision is not applicable-Special rate of tax inapplicable-Statement under section 131 is no evidentiary value in absence of corroborative evidence-Entries in the Diary-No supporting evidence-Addition is not valid. [S.69A, 115BBE, 131, 133A]