NIH:10.7863/ultra.14.08033
NIH:10.7863/ultra.15.08035
NIH:10.7863/ultra.15.09087
NIH:10.7863/ultra.16.01081
NIH:10.7863/ultra.16.01082
NIH:10.7863/ultra.33.5.745
NIH:10.7863/ultra.33.7.1217
NIH:10.7863/ultra.33.10.1877
NIH:10.7863/ultra.33.12.2187