Citing multiple publications by same author in same year in RMarkdown

Question

I have two citations by the same author, and they were published in the same year.

Right now, my code looks like this

blah blah Hansen [-@Hansen2015a; -@Hansen2015b]

and I get this

blah blah Author (2015; 2015) blah blah

I want the result to look like this

blah blah Author (2015a, 2015b) blah blah

In my case, I want to cite both publications in the same sentence, but I also want to know how to achieve this lettering if I were to cite these publications in different sentences.

I tried editing the year in the BibTeX citation entry to manually insert the a and b, but that results in this

blah blah Author (n.d.; n.d.) blah blah

Bornstein

Answer 1

Hi mdawgig and welcome to Stack Overflow!
Here are two examples of what the entries (same author, same year) in BibTeX file (.bib) might look like:

@article{Author_2015a,
    Author = {Author, A. and Another, B.},
    Journal = {Amazing Journal},
    Pages = {50-100},
    Title = {A New Paper},
    Volume = {5},
    Year = {2015}
}

@article{Author_2015b,
    Author = {Author, A. and Another, C.},
    Journal = {Another Amazing Journal},
    Pages = {100-150},
    Title = {Another New Paper},
    Volume = {7},
    Year = {2015}
}

In R Markdown document, a line like this:

# using minus ( - ) sign before the @ will suppress author's name  
blah blah Author [-@Author_2015a; -@Author_2015b] blah blah

should return desired result (citing both publications in the same sentence):

blah blah Author (2015a, 2015b) blah blah

I also want to know how to achieve this lettering if I were to cite these publications in different sentences.

There are many R Markdown resources out there. You may find some of these useful (Bibliographies and Citations, Bibliographies, Bibliographies and citations, Citations).

Let us know if this answer your question.

Underproduction

Thanks for the reply, but my .bib file and R Markdown references look like that as far as I can tell, but the error persists. Both .bib are like: @Article{Hansen2015a, author = {Hansen, Gretchen and Carpenter, Stephen and Gaeta, Jereme and Hennessy, Joseph and Vander Zanden, Jake}, journal = {Canadian Journal of Fisheries and Aquatic Sciences}, title = {Predicting walleye recruitment as a tool for prioritizing management actions}, year = {2015}, pages = {661-672}, volume = {72}, } In-text: in Hansen et al. [-@Hansen2015a; -@Hansen2015b] – Bornstein

I can perfectly reproduce your citations. As far as i know, Pandoc generates citations in R Markdown documents. Do you have Rstudio updated (also, rmarkdown and knitr packages)? – Caporetto

My rmarkdown and knitr were up to date, but I did update Rstudio to no avail. The output remains Hansen et al. (2015; 2015). – Bornstein

Did you try installing RStudio Preview? It will automatically includes/download latest Pandoc version. – Caporetto

I updated to Preview and the citations are the same. – Bornstein

Just to be clear, do you have both references: @Article{Hansen2015a, ... } and @Article{Hansen2015b, ... } in the same .bib file with the same year = {2015}? – Caporetto

That is correct. Same file, year is {2015} for both. – Bornstein

It's just an hint... open your .bib file with RStudio, then go to menu: File > Save with Encoding... and then choose UTF-8 encoding as default. Knit your .Rmd file... – Caporetto

Also, try creating the essential .Rmd and minimal .bib file (just containing examples above)... – Caporetto

Well, I think I've identified the source of the problem. I had forgotten since I put the citation in that the two papers don't have the exact same set of authors; the second has all the same authors and one additional author. Thus, even though they both have the same in-text citation for author (Hansen et al.), they technically do not have the same authors, and thus RMarkdown seems to be acting correctly when it outputs (2015; 2015). My problem has gone from a technical one to a citation style guide one. Thanks; compiling a minimal .bib file is what made me catch on to this. – Bornstein