Azollaceae
- Description of this group of small, free-floating aquatic ferns. From the aquatic pteridophytes of Papua New Guinea.
- http://www.anbg.gov.au/fern/aquatic/azollaceae.html

Genus List
- Royal Botanic Gardens, Kew, England.
- http://www.rbgkew.org.uk/cgi-bin/web.dbs/genlist.pl?AZOLLACEAE