How can I find out more information about a specific architect (McElroy) who built contemporary houses in Pennsylvania?

The website of the Philadelphia Architects and Buildings website lists a Charles B. McElroy in their architect search <a rel="nofollow" href="http://www.philadelphiabuildings.org/pab/index.cfm">http://www.philadelphiabuildings.org/pab/index.cfm</a> There is no biography of him listed, however. I would contact the organization for further assistance- If you have general questions about the PAB Project, contact Bruce Laverty, Project Director, at the Athenæum by calling 215-925-2688. For questions and comments concerning specific biographies, buildings or images in the database, please use the feedback feature, which is located in the menu on the left side of each page. <a rel="nofollow" href="http://www.philadelphiabuildings.org/pab/feedback.cfm?Page=/pab/about.cfm">http://www.philadelphiabuildings.org/pab/feedback.cfm?Page=/pab/about.cfm</a> Also consider contacting the Philadelphia Library <a rel="nofollow" href="http://www.library.phila.gov/">http://www.library.phila.gov/</a> Thank ...  more