AP follows a different style, IIRC. This stuff is all kind of arbitrary and depends on particular publisher style. Where I work we drop the last s.
--- On Fri, 9/4/09, Michael Pollak <mpollak at panix.com> wrote:
> From: Michael Pollak <mpollak at panix.com>
> Subject: Re: [lbo-talk] baby thoughts
> To: lbo-talk at lbo-talk.org
> Date: Friday, September 4, 2009, 10:32 AM
>
> On Sep 4, 2009, at 9:52 AM, shag carpet bomb wrote:
>
> > srsly? back when I was publishing on habermas, i did a
> massive inquiry as to which was the ultimately correct
> approach: habermas' or habermas's. it bugged me that i could
> never find a definitive answer.
>
> FWIW, this is the very first rule in _The Elements of
> Style_ by Strunk & White, everyone's favorite tiny
> quotable grammar authority:
>
> <begin excerpt>
>
> 1. Form the possessive singular of nouns by adding
> 's.
>
> Follow this rule whatever the final consonant. Thus
> write,
>
> Charles's friend
> Burns's poems
> the witch's malice
>
> Exceptions are the possessives of ancient proper names
> ending in -es and -is, the possessive *Jesus'*, and such
> forms as *for conscience' sake*, *for righteousness'*
> sake. But such forms as *Moses' Laws*, *Isis' temple*
> are commonly replaced by
>
> the laws of Moses
> the temple of Isis
>
> <end excerpt>
>
> Michael
>
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