Nielsen, S. N., & Briann D. Fath and other. (2020). A New Ecology system perspective (second edition.). Elsevier.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিNielsen, Soren Nors, এবং Briann D. Fath and other. A New Ecology System Perspective. second edition. united Kingdom: Elsevier, 2020.
M.L.A (9 ম সংস্করণ) উদ্ধৃতিNielsen, Soren Nors, এবং Briann D. Fath and other. A New Ecology System Perspective. second edition. Elsevier, 2020.