Reference

M. L. Porto, J. E. A. Mariath, M. L. Detoni, S. S. Cavalli, H. Winge, Friedrich Ehrendorfer (1977): New Species of Relbunium (Rubiaceae) From Brazil, With Notes on Flavonoid and Peroxidase Patterns * – Österreichische Botanische Zeitschrift = Plant Systematics and Evolution – 128: 177 - 193.