You can find encyclopedias in Educat+ using the following search query string:
"[your subject] -- Encyclopedias"
Use the searching by subject guide to locate the specific controlled vocabulary for your subject subject of interest.
Columbia University Libraries
In CLIO Databases, adjust the field "Browse by Research Type" to "Encyclopedias" and search for the topic you are looking for. You can also adjust the "Browse by Discipline" field to narrow your results.