- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
"The development of the series Bolivinoides strigillata- decorata-australis-gigantea in the upper Cretaceous of Belgium is followed. In a nearly continuous sequence of formations, the group is found to increase the number of pustules on the last-formed sutures from two to nine. This continuous increase can be used as a stratigraphic tool in working out chronology from the lower Campanian to the uppermost Maestrichtian in northwestern Europe. In other areas where the same sequence of species, or parts of the sequence, are found, it can be applied in stratigraphy in the same manner."