Malaysian Freshwater Oligochaetes
A table of freshwater Oligochaete occurrences in Malaysian rivers and lakes.

Oligochaeta
A nice summary of the families of freshwater Oligochaetes found in North America.

Earthworm Biology and Production
Information circular from University of Florida, Institute of Food and Agricultural Sciences.

Earthworm Information
Extensive information about individual species, ecology and biology, and role in agriculture.