original description(ofPolymorphina (Guttulina) costatula Galloway & Wissler, 1927 †)Galloway, J. J.; Wissler, S. G. (1927). Pleistocene Foraminifera from the Lomita Quarry Palos Verdes Hills, California. <em>Journal of Paleontology.</em> 1: 35-87. page(s): p. 57 pl. 9 fig. 10 [details] Available for editors [request]
new combination referenceCushman, J. A.; Ozawa, Y. (1930). A Monograph of the Foraminiferal Family Polymorphinidae, Recent; Fossil. <em>Proceedings of the United States National Museum.</em> 77: 1-185., available online athttp://www.biodiversitylibrary.org/page/32382238#page/199/[details] Available for editors [request]