Organisation for Economic Co-operation and Development & ProQuest (Firm). (2009). Poland. Organisation for Economic Co-operation and Development.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Organisation for Economic Co-operation and Development و ProQuest (Firm). Poland. Paris: Organisation for Economic Co-operation and Development, 2009.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Organisation for Economic Co-operation and Development و ProQuest (Firm). Poland. Organisation for Economic Co-operation and Development, 2009.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.