S. 263 : Commissioner-Revision of orders prejudicial to revenue-Reassessment-Lack of proper enquiry-Issues not subject-matter of reassessment-Issue which is not subject matter of reassessment, Commissioner cannot direct the Assessing Officer to carry out the enquiry as suggested by the Commissioner. [S. 37(1), 40A(2)(vi), 40A(2)(b), 147, 148]