What is an encyclopedia?
An encyclopedia is a resource which provides concise information on many subjects or on many aspects of one subject. It is composed of entries or articles, arranged alphabetically or thematically. Encyclopedias are concerned with factual information. The summaries in an encyclopedia are drawn from research and each entry is usually accompanied by a list of citation references to relevant research.
Encyclopedias for Folklore Studies
Enzyklopädie des Märchens
R. W. Brednich, editor
2015, fifteen volumes
The Greenwood Encyclopedia of World Folklore and Folklife
William M. Clements, editor
2006, four volumes

Encyclopedia of Folklore and Literature
Mary Ellen Brown & Bruce A. Rosenberg, editors
1998

New Larousse Encyclopedia of Mythology
Felix Guirand, editor
1968
An Encyclopedia of Fairies
Katherine Mary Briggs
1976
The Greenwood Encyclopedia of Folktales and Fairy Tales
Donald Haase, editor
2008