Backward area designation clarified: prior schedule areas retain tax benefit for qualifying industrial undertakings and hotels started before amendment. The amendment omitted the Eighth Schedule and authorized the Central Government to specify backward area by notification, with limited retrospective effect; notwithstanding that notification, areas specified in the omitted Schedule continue to qualify for the tax incentive for industrial undertakings and hotels that began operations before the amendment's assent. District references in the notification apply to their earlier boundaries, and a typographical district name error is corrected.