Howard, Hildegarde; Johnson, Ned K.; Rabor, D. S.; Rand, A. L.; Bohl, Wayne H.; Traylor, Elmo; Parkes, Kenneth C.; Orr, Robert T.; Kilham, Lawrence (1958). «From Field and Study». The Condor. 60 (2): 136–142. ISSN1938-5129. doi:10.2307/1365270
Howard, Hildegarde; Johnson, Ned K.; Rabor, D. S.; Rand, A. L.; Bohl, Wayne H.; Traylor, Elmo; Parkes, Kenneth C.; Orr, Robert T.; Kilham, Lawrence (1958). «From Field and Study». The Condor. 60 (2): 136–142. ISSN1938-5129. doi:10.2307/1365270
Howard, Hildegarde; Johnson, Ned K.; Rabor, D. S.; Rand, A. L.; Bohl, Wayne H.; Traylor, Elmo; Parkes, Kenneth C.; Orr, Robert T.; Kilham, Lawrence (1958). «From Field and Study». The Condor. 60 (2): 136–142. ISSN1938-5129. doi:10.2307/1365270