@article{24818,
      author = {Hurd, Paul D.},
      url = {http://library.usi.edu/record/24818},
      title = {Principal sunflower bees of North America with emphasis on  the Southwestern United States (Hymenoptera, Apoidea) /},
      publisher = {Smithsonian Institution Press,},
      recid = {24818},
      pages = {iii, 158 p. :},
      address = {Washington :},
      year = {1980},
}