National Arborist Association. (2000). Basic training for ground operations in tree care workbook. New York: International Society of Arboriculture and National Arborist Association.
Chicago Style aipamenaNational Arborist Association. Basic Training for Ground Operations in Tree Care Workbook. New York: International Society of Arboriculture and National Arborist Association, 2000.
MLA aipamenaNational Arborist Association. Basic Training for Ground Operations in Tree Care Workbook. New York: International Society of Arboriculture and National Arborist Association, 2000.
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