Reference

Alice L. Hempel, Patrick A. Reeves, Richard G. Olmstead, Robert K. Jansen (1995): Implications of rbcL sequence data for higher order relationships of the Loasaceae and the anomalous aquatic plant Hydrostachys (Hydrostachyaceae) – Österreichische Botanische Zeitschrift = Plant Systematics and Evolution – 194: 25 - 37.