Cresson, E. T. Sr. 1916. The Cresson types of Hymenoptera. Memoirs of the American Entomological Society 1:1-141.
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Cresson, E. T. Jr. 1928. The types of Hymenoptera in the Academy of Natural Sciences of Philadelphia other than those of Ezra T. Cresson. Memoirs of the American Entomological Society 5:1-90.
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