referenceCitation: @article{mcgregor_insect_1976,  title = {Insect pollination of cultivated crop plants},  url = {https://handle.nal.usda.gov/10113/CAT76674944},  language = {English},  author = {McGregor, Samuel Emmett},  translator = {McGregor, Samuel Emmett},  year = {1976},  keywords = {Bee culture, Bees, Fertilization of plants by insects, Plants, Cultivated},  pages = {viii, 411 p. : ill. ; 30 cm.--USDA}, }