unknown. (2020). Factors affecting contingency amount in bidding for large construction projects: Contractors perspective.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)unknown. Factors Affecting Contingency Amount in Bidding for Large Construction Projects: Contractors Perspective. 2020.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)unknown. Factors Affecting Contingency Amount in Bidding for Large Construction Projects: Contractors Perspective. 2020.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.