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Bushmann, Sara L.; Drummond, Francis A. (August 2015). "Abundance and Diversity of Wild Bees (Hymenoptera: Apoidea) Found in Lowbush Blueberry Growing Regions of Downeast Maine". Environmental Entomology. 44 (4): 975–989. doi:10.1093/ee/nvv082. ISSN1938-2936. PMID26314043.
Bushmann, Sara L.; Drummond, Francis A. (August 2015). "Abundance and Diversity of Wild Bees (Hymenoptera: Apoidea) Found in Lowbush Blueberry Growing Regions of Downeast Maine". Environmental Entomology. 44 (4): 975–989. doi:10.1093/ee/nvv082. ISSN1938-2936. PMID26314043.