Commission Regulation (EC) No 2048/97 of 20 October 1997 amending Regulations (EC) No 936/97 opening and providing for the administration of tariff quotas for high-quality fresh, chilled and frozen beef and for frozen buffalo meat and (EC) No 996/97 on the opening and administration of an import tariff quota for frozen thin skirt of bovine animals falling within CN code 0206 29 91