Thanks. Others I've checked all agree.

I had missed your earlier response on this issue ("The sentence should still be grammatically correct without the parenthetical information.” ), with which I fully concur. I haven’t been able to trace the source of this ill-formed construction and am hoping you could confirm that no guides endorse this.

Do you know of any style guide that permits this citation format: (Smith and Wexwood 2010) reported an increase in the number of books read, whereas (Gibson 2011) reported a decrease. (Albright, Wayne, and Fortinbras 2004) found no significant results. with cites in parentheses as integral parts of the sentence rather than as supporting data. I have seen this in various venues, mostly technical conference papers. Search as I might, I cannot locate any guide that supports this.