# Citation collapsing question

**URL:** <https://discourse.citationstyles.org/t/citation-collapsing-question/946>\
**Category:** CSL Development\
**Created:** [February 5, 2011, 3:28am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946 "2011-02-05T03:28:43Z")\
**Posts on this page:** 15\
**Page:** 1

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**Author:** ![Frank\_Bennett](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/frank_bennett/32/198_2.png) [@Frank\_Bennett](https://discourse.citationstyles.org/u/Frank_Bennett)\
**Post date:** [February 5, 2011, 3:28am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/1 "2011-02-05T03:28:43Z")

</div>

We have a query that arises from this thread:

> **[Citations not collapsing](https://forums.zotero.org/discussion/16284/citations-not-collapsing/)**
>
> Hello,
> 
> I made some simple mods to the example in http://citationstyles.org/downloads/primer.html to add:

The issue is whether, when collapse=“year” is set, citations should  
collapse when the visual appearance of two successive name lists is  
identical after et al. truncation, but the underlying name lists  
differ.

I think the user and adamsmith are probably right on this one, but I’d  
like to poll folks for views before making the necessary change. What  
does everyone think about this one?

Frank

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**Author:** ![Rintze\_Zelle](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/rintze_zelle/32/175_2.png) [@Rintze\_Zelle](https://discourse.citationstyles.org/u/Rintze_Zelle)\
**Post date:** [February 5, 2011, 3:47am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/2 "2011-02-05T03:47:57Z")

</div>

You have perfect timing. A post from today:

[http://blog.apastyle.org/apastyle/2011/02/et-al-when-and-how.html](http://blog.apastyle.org/apastyle/2011/02/et-al-when-and-how.html)

I’d suggest pinging the APA people.

RintzeOn Fri, Feb 4, 2011 at 10:28 PM, Frank Bennett \<@Frank\_Bennett\>wrote:

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<div class="post-metadata">

**Author:** ![Frank\_Bennett](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/frank_bennett/32/198_2.png) [@Frank\_Bennett](https://discourse.citationstyles.org/u/Frank_Bennett)\
**Post date:** [February 5, 2011, 4:14am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/3 "2011-02-05T04:14:17Z")

</div>

> You have perfect timing. A post from today:
> 
> [http://blog.apastyle.org/apastyle/2011/02/et-al-when-and-how.html](http://blog.apastyle.org/apastyle/2011/02/et-al-when-and-how.html)
> 
> I’d suggest pinging the APA people.

Great. Unfortunately, signing into their typepad system via Google or  
Twitter sends my browser into a weird race condition. The thing keeps  
losing keystrokes until the browser threatens to consume all of the  
memory in my machine. Odd, but fatal.

Sorry to be reliant on this one. Pointers (on the style issue) welcome.

Frank

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**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [February 5, 2011, 2:18pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/4 "2011-02-05T14:18:30Z")

</div>

As I just posted on that thread, I disagree. I don’t think this is a bug.

Bruce

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**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [February 5, 2011, 3:11pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/5 "2011-02-05T15:11:39Z")

</div>

Based on subsequent discussion on that thread, I think we probably  
need to amend the spec to include more detail on the processing  
expectations, add a new attribute (“sort-author-names-as” --\>  
“full-name-string” | “shortened form”?), and update the test suite  
accordingly.

Ugh … I can imagine this is a PITA to program.

Bruce

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**Author:** ![Frank\_Bennett](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/frank_bennett/32/198_2.png) [@Frank\_Bennett](https://discourse.citationstyles.org/u/Frank_Bennett)\
**Post date:** [February 5, 2011, 4:19pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/6 "2011-02-05T16:19:27Z")

</div>

> > > We have a query that arises from this thread:
> > > 
> > > [Citations not collapsing - Zotero Forums](http://forums.zotero.org/discussion/16284/citations-not-collapsing/)
> > > 
> > > The issue is whether, when collapse=“year” is set, citations should  
> > > collapse when the visual appearance of two successive name lists is  
> > > identical after et al. truncation, but the underlying name lists  
> > > differ.
> > > 
> > > I think the user and adamsmith are probably right on this one, but I’d  
> > > like to poll folks for views before making the necessary change. What  
> > > does everyone think about this one?
> > 
> > As I just posted on that thread, I disagree. I don’t think this is a bug.
> 
> Based on subsequent discussion on that thread, I think we probably  
> need to amend the spec to include more detail on the processing  
> expectations, add a new attribute (“sort-author-names-as” →   
> “full-name-string” | “shortened form”?), and update the test suite  
> accordingly.

I don’t see anything in that thread about sorting behavior.

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**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [February 5, 2011, 4:45pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/7 "2011-02-05T16:45:13Z")

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<div class="post-metadata">

**Author:** ![Frank\_Bennett](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/frank_bennett/32/198_2.png) [@Frank\_Bennett](https://discourse.citationstyles.org/u/Frank_Bennett)\
**Post date:** [February 6, 2011, 1:25am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/8 "2011-02-06T01:25:31Z")

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<div class="post-metadata">

**Author:** ![Frank\_Bennett](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/frank_bennett/32/198_2.png) [@Frank\_Bennett](https://discourse.citationstyles.org/u/Frank_Bennett)\
**Post date:** [February 6, 2011, 1:27am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/9 "2011-02-06T01:27:20Z")

</div>

The above should have read, “that the grouped references be sorted in  
the order of the earliest-dated item in each.”

Frank

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<div class="post-metadata">

**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [February 6, 2011, 1:58am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/10 "2011-02-06T01:58:39Z")

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<div class="post-metadata">

**Author:** ![Frank\_Bennett](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.citationstyles.org/frank_bennett/32/198_2.png) [@Frank\_Bennett](https://discourse.citationstyles.org/u/Frank_Bennett)\
**Post date:** [February 6, 2011, 2:39am UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/11 "2011-02-06T02:39:43Z")

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<div class="post-metadata">

**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [February 6, 2011, 3:31pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/12 "2011-02-06T15:31:42Z")

</div>

Awesome!

So where did we get off the rails here? E.g. are we all OK, or is  
there still something to resolve?

Bruce

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**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [February 9, 2011, 2:07pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/13 "2011-02-09T14:07:25Z")

</div>

Sorry I’m joining in so late… well, Bruce supposed output is not  
entirely correct. It should instead be:

```
John Doe and Steve Jones, 2000a, Three Title
John Doe and Steve Jones, 2000b, Four Title
John Doe and Jane Smith, 2000c, One Title
John Doe and Jane Smith, 2000d, Two Title

```

In a citation year-suffix collapsing would occur: Doe et al 2000a-d.

I’m attaching a couple of tests to show this behavior. I didn’t test  
them with citeproc-js but I believe they should pass with it too.

Andrea

[collapse\_YearSuffixCollapseDifferentAuthors.txt](https://canada1.discourse-cdn.com/flex029/uploads/citationstyles/original/1X/1fa7f1ec75c1e787fd1fae3f507617719b1be120.txt) (3.54 KB)

[collapse\_YearSuffixCollapseDifferentAuthorsBibliography.txt](https://canada1.discourse-cdn.com/flex029/uploads/citationstyles/original/1X/0e30ae8508e58b3a84552be3c85b5f2ced062f71.txt) (3.83 KB)

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<div class="post-metadata">

**Author:** ![Bruce\_D\_Arcus1](https://avatars.discourse-cdn.com/v4/letter/b/4bbf92/32.png) [@Bruce\_D\_Arcus1](https://discourse.citationstyles.org/u/Bruce_D_Arcus1)\
**Post date:** [February 10, 2011, 4:31pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/14 "2011-02-10T16:31:41Z")

</div>

Andrea,

> > > > > Standard author-date style in my view:
> > > > > 
> > > > > 1. sort and group (by author name string, and then year) reference  
> > > > > list (where collapsing does not apply)
> > > > > 2. attach an index to each item within the year sub-group
> > > > > 3. dump the reference list to formatted string
> > > > > 4. render citation reference suffix by referencing 2; et al collapsing  
> > > > > happens here, based on 2
> > > > > 
> > > > > Admittedly CSL has evolved considerably since then, but it seems to me  
> > > > > that’s the fundamental logic of how citations work.
> > > 
> > > We have, let’s say, four items, all with the same first author, but  
> > > some with different second authors.
> > > 
> > > John Doe and Jane Smith, 2000, One Title  
> > > John Doe and Jane Smith, 2000, Two Title  
> > > John Doe and Steve Jones, 2000, Three Title  
> > > John Doe and Steve Jones, 2000, Four Title
> > > 
> > > And let’s say we have a style that always says to use et al for  
> > > everything but the first author.
> > > 
> > > Questions:
> > > 
> > > a) how are those sorted?  
> > > b) what are their suffix values?
> > > 
> > > Aside: there may be a secondary question about what’s a subsequent  
> > > author item in this list, but let’s leaves aside.
> > > 
> > > My argument is:
> > > 
> > > John Doe and Steve Jones, 2000a, Three Title  
> > > John Doe and Steve Jones, 2000b, Four Title  
> > > John Doe and Jane Smith, 2000a, One Title  
> > > John Doe and Jane Smith, 2000b, Two Title
> > 
> > Not at all, that’s exactly what the citeproc-js will produce. Andrea  
> > can confirm, but from past discussions I’m sure that the same is true  
> > of citeproc-hs.
> > 
> > So a bright spot in the day. 🙂
> 
> Sorry I’m joining in so late… well, Bruce supposed output is not  
> entirely correct. It should instead be:
> 
> John Doe and Steve Jones, 2000a, Three Title  
> John Doe and Steve Jones, 2000b, Four Title  
> John Doe and Jane Smith, 2000c, One Title  
> John Doe and Jane Smith, 2000d, Two Title

What do you mean by “not … correct”?

I am telling you that a test created according to the scenario I  
presented here should fail with the example output you provided.

“John Doe and Steve Jones” and “John Doe and Jane Smith” are two  
different “authors” (really author groups).

So if we have a disagreement here, then my worry that we have a  
problem is in fact true.

Bruce

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**Author:** ![Andrea\_Rossato1](https://avatars.discourse-cdn.com/v4/letter/a/e47774/32.png) [@Andrea\_Rossato1](https://discourse.citationstyles.org/u/Andrea_Rossato1)\
**Post date:** [February 10, 2011, 7:55pm UTC](https://discourse.citationstyles.org/t/citation-collapsing-question/946/15 "2011-02-10T19:55:47Z")

</div>

Bruce,

> Andrea,
> 
> > > > My argument is:
> > > > 
> > > > John Doe and Steve Jones, 2000a, Three Title  
> > > > John Doe and Steve Jones, 2000b, Four Title  
> > > > John Doe and Jane Smith, 2000a, One Title  
> > > > John Doe and Jane Smith, 2000b, Two Title
> > > 
> > > Not at all, that’s exactly what the citeproc-js will produce. Andrea  
> > > can confirm, but from past discussions I’m sure that the same is true  
> > > of citeproc-hs.
> > 
> > Sorry I’m joining in so late… well, Bruce supposed output is not  
> > entirely correct. It should instead be:
> > 
> > John Doe and Steve Jones, 2000a, Three Title  
> > John Doe and Steve Jones, 2000b, Four Title  
> > John Doe and Jane Smith, 2000c, One Title  
> > John Doe and Jane Smith, 2000d, Two Title
> 
> What do you mean by “not … correct”?
> 
> I am telling you that a test created according to the scenario I  
> presented here should fail with the example output you provided.
> 
> “John Doe and Steve Jones” and “John Doe and Jane Smith” are two  
> different “authors” (really author groups).
> 
> So if we have a disagreement here, then my worry that we have a  
> problem is in fact true.

you seem to be right, there must be some disagreement, and I  
understand it because in citeproc-hs-0.2 year-suffix disambiguation  
worked the way you described above. So I had to change it in the  
transition to 0.3 in order comply with the specification, with  
citeproc-js and a specific test of the test-suite:

[https://bitbucket.org/bdarcus/citeproc-test/src/1a2a481c8130/processor-tests/humans/disambiguate\_YearSuffixAndSort.txt](https://bitbucket.org/bdarcus/citeproc-test/src/1a2a481c8130/processor-tests/humans/disambiguate_YearSuffixAndSort.txt)

> The spec is also silent on the details, and so leaves room for these  
> different understandings.

You are wrong, I think. And I think Frank implemented it in strict  
adherence of the specification wording:

```
«[...] year-suffix is added to cites that are otherwise identical
(e.g. "Doe 2007, Doe 2007" becomes "Doe 2007a, Doe 2007b").»

```

As you see no mention is made about cites having the same  
contributors’ list, but even the example seems to refer to John Doe  
2007 and Jane Doe 2007 (see above “disambiguate-add-givenname” in the  
same box).

In a style using short names different authors could be disambiguated  
with year-suffixes. The same apply with different authors groups when  
et-al is used without name and givenname disambiguation.

I changed citeproc-hs to reflect the new behavior because it makes  
sense to me. I thought it was a deliberate decision…

Andrea