Ackerman, Daniel; Breen, Amy (2016-06-06). "Infrastructure Development Accelerates Range Expansion of Trembling Aspen ( Populus tremuloides, Salicaceae) into the Arctic". Arctic (dalam bahasa Inggris). 69 (2): 130–136. doi:10.14430/arctic4560. ISSN1923-1245.
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Ackerman, Daniel; Breen, Amy (2016-06-06). "Infrastructure Development Accelerates Range Expansion of Trembling Aspen ( Populus tremuloides, Salicaceae) into the Arctic". Arctic (dalam bahasa Inggris). 69 (2): 130–136. doi:10.14430/arctic4560. ISSN1923-1245.