1. Stable Isotope Program, U.S. Department of Agriculture, Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX 77030
2. U.S. Department of the Interior, National Park Service, Federal Building Room 474, Lincoln, NE 68508
3. Center for Archaeological Research, Southwest Missouri State University, Naylor, MO 63953
4. Department of Biology, Augustana College, Sioux Falls, SD 57197