Every entry in this dictionary is annotated with a one or more sources.
A source may be an English-Esperanto dictionary, an Esperanto-English dictionary, an Esperanto textbook, a translation, or simply someone's idea of a good definition.
For example, the sources for a particular definiton may be 'CEED' and 'Revo'. This indicates that the definition can be found in those dictionaries.
The reader can use the sources to determine how trustworthy a particular definition is.