Kirkbride, Joseph H., Jr. 1977. "Index to the Rubiaceae by Julian A. Steyermark in the Botany of the Guayana Highland by B. Maguire and Collaborators." Phytologia, 36 324–366.
Terrell, Edward E., Reveal, J. L., Spjut, R. W., Witcomb, R. F., Kirkbride, Joseph H., Jr., Cimino, M. T., and Strong, Mark T. 2000. Annotated list of the flora of the Beltsville Agricultural Research Center, Beltsville, Maryland. U.S. Department of Agriculture, Agricultural Research Service.
(81-84) Requests for binding decisions on the descriptive statements associated with Cinchona cordifolia, C. lancifolia, C. oblongifolia, and C. ovalifolia (Rubiaceae)
Delprete, Piero G. and Kirkbride, Joseph H., Jr. 2017. "Schradera involucrata is the correct name for Spermacoce scandens (Rubiaceae)." Journal of the Botanical Research Institute of Texas, 11, (1) 121–122.
Delprete, Piero G. and Kirkbride, Joseph H., Jr. 2016. "New combinations and new names in Palicourea (Rubiaceae for species of Psychotria subgenus Heteropsychotria occurring in the Guianas)." Journal of the Botanical Research Institute of Texas, 10, (2) 409–442.