A side note, how do you go through a reference and lift all the information from it while avoiding simply paraphrasing it? Or are you using it as a starting point then finding more sources on these mayors?
In the case of the ADB, it's public domain (published in the late 19th century), so could be used directly, like the 1911 Britannica is. Except it's in German, so some translation is necessary. :) I sometimes translate fairly directly, but I usually look for whether there are any more recent sources to expand on the bio, or correct any info that might now be obsolete.
With copyrighted encyclopedias, my preference is to use at least 2-3 sources for a bio. For example, with a physicist, I'd use a biographical dictionary / encyclopedia as a reference for basic biographical facts (dates, locations, awards, etc.), and then flesh out information about scientific importance from something like a textbook or survey paper commenting on his/her work.
If the main source is a non-encyclopedia, it's usually less of a problem, because the original text doesn't really read like an encyclopedia article anyway. For example, when writing articles on Greek archaeological sites, my source material is usually a discussion in a monograph or history book, which is sometimes scattered (it may be mentioned for a few pages in Chapter 2, then again in Ch. 8, sometimes as a main topic, other times in passing when discussing an event or person, that kind of thing). So it's a matter of going through, noting down salient facts and page numbers they came from, and then assembling the results into an article.
