Organisation of Professional Associations of Sri Lanka. (1986). O.P.A. journal: The official publication of the Organization of Professional Associations of Sri Lanka. OPA.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Organisation of Professional Associations of Sri Lanka. O.P.A. Journal: The Official Publication of the Organization of Professional Associations of Sri Lanka. [Colombo]: OPA, 1986.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Organisation of Professional Associations of Sri Lanka. O.P.A. Journal: The Official Publication of the Organization of Professional Associations of Sri Lanka. OPA, 1986.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.