New Reference Search Tool

I just discovered Reference Search: Explicit Searches on Implicit References. This new search engine only works to search references to biblical/early Xn/rabbinic texts. (Check out the Reference List of works it is cataloging.) It will not direct to you online versions of those texts. It will find articles that mention that specific text. One can be as specific (i.e., a verse) or broad (i.e., a whole document) as one wants. The search engine also is so astute that if you are looking for, for example, Mark 6:34, it will also return hits that refer to Mark 6 in general or ones like Mark 6:32-35 that include that verse. (Note that you apparently must use a colon for the ch:verse designation.)
This search engine does not scan the whole web. It returned hits from such sites as: biblestudy.org; bible.org (including net.bible.org) jerusalemperspective.com; ccel.org; mindspring.com; ntgateway.com; crosswalk.com; usccb.org. A few others may be included, but those were the main ones I noticed.
You will definitely want to check it out.