1. Aquatic Plant Book;Cook,1990
2. Aquatic and Wetland Plants of India;Cook,1996
3. Etude sur les Podostemales. 10. Structures florales et végétatives des Tristichaceae;Cusset;Adansonia,1988
4. A new classification of water plant communities;Den Hartog;Acta. Bot. Neerl.,1964
5. Plant Anatomy;Esau,1972