Section 9(1)(a) in The Orissa Statistics and Economics Service Rules, 1979
(a)he must be a citizen of India or a displaced person from the former East Pakistan who has migrated to India on or after the first January, 1964 or a repatriate from Burma/Ceylone who has migrated to India on or after the 1st June, 1963/1st November, 1964, or a subject of Nepal, Bhutan or Sikkim;