Encyclopedia of medieval philosophy : philosophy between 500 and 1500 by 
Encyclopedia of early modern philosophy and the sciences by 
The Oxford Handbook of Philosophy of Religion by
Encyclopedia of Religion by 
The New Schaff-Herzog Encyclopedia of Religious Knowledge by 
Encyclopedia of Buddhism by 
New Catholic Encyclopedia by 
Encyclopedia of Islam and the Muslim World by 
Encyclopedia of Islam in the United States by 
Encyclopedia Judaica by 
Encyclopedia of Monasticism by 
Encyclopedia of Native American Shamanism by 
Encyclopedia of Protestantism by 
A Dictionary of Comparative Religion by 
Abingdon Dictionary of Living Religions by Sometimes you want to find other articles or books that will cite a particular work by an author. Fortunately, there are specialized tools that can do this, often refered to as 'citation indexes'.
Depending on the citation practices of a particular field of study, these citations may be primarily in (and to) journal article or books, and different citation indexes do a better job with each. Two are recommended below:
This link opens in a new windowClick on link at bottom to view results in Google Books. When in Google Books, use 'Find in a Library' to see nearby libraries that may have the full book.
