Singh, G., & Inderjeet Kaur Sethi. (1992). Topics and terms in enviornmental science. Commonwealth.
استشهاد بنمط شيكاغوSingh, Gurcharan, و Inderjeet Kaur Sethi. Topics and Terms in Enviornmental Science. New Delhi: Commonwealth, 1992.
MLA استشهادSingh, Gurcharan, و Inderjeet Kaur Sethi. Topics and Terms in Enviornmental Science. Commonwealth, 1992.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.