Voss, J. H., & Killip, T. (1980). Cooperation and market penetration: Transformations in indigenous forms of cooperation on the Cordillera central of the Philippines.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Voss, Joachim Heinrich, و Tom Killip. Cooperation and Market Penetration: Transformations in Indigenous Forms of Cooperation on the Cordillera Central of the Philippines. 1980.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Voss, Joachim Heinrich, و Tom Killip. Cooperation and Market Penetration: Transformations in Indigenous Forms of Cooperation on the Cordillera Central of the Philippines. 1980.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.