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توثيق جمعية علم النفس الأمريكية APA (الطبعة السابعة)

Alwelaie, A. N. A., & Carl L. Hansen. (1985). The Role of Natural and Human Factors in The Degradation of The Environment in Central, Eastern, and Northern Saudi Arabia. University of California, Department of Geography.

توثيق أسلوب شيكاغو (الطبعة السابعة عشر)

Alwelaie, Abdullah Nasser Ali, و Carl L. Hansen. The Role of Natural and Human Factors in The Degradation of The Environment in Central, Eastern, and Northern Saudi Arabia. California, (U S A): University of California, Department of Geography, 1985.

توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)

Alwelaie, Abdullah Nasser Ali, و Carl L. Hansen. The Role of Natural and Human Factors in The Degradation of The Environment in Central, Eastern, and Northern Saudi Arabia. University of California, Department of Geography, 1985.