Anti-dumping duty on calcined gypsum powder imposed; duty equals difference between landed value and reference price for specified origins. Imposition of anti-dumping duty on calcined gypsum powder (heading 2520) from Iran, Oman, Saudi Arabia and UAE, calculated as the difference between the customs-assessed landed value and specified reference prices set per metric tonne in the notification where landed value is less than the reference price; duty payable in Indian currency and effective for five years. The notification defines landed value and prescribes the government-notified exchange rate with the bill-of-entry date as the relevant conversion date.