I have a reference containing a name: Hornbaek. The author's used a ligature when writing their name. The citation uses Hornb\aek, which doesn't work in the bibliography, but does work in text. Here's an example:



 author = {Rasmussen, Majken K. and Pedersen, Esben W. and Petersen, Marianne G. and Hornb\aek, Kasper},
 title = {Shape-changing interfaces: a review of the design space and open research questions},
 booktitle = {Proceedings of the SIGCHI Conference on Human Factors in Computing Systems},


Here's a ligature: \ae


This doesn't work - it gives this error:

! Undefined control sequence.
l.5 Hornb\aek

but if the \ae are removed from the citation, the correct ligature is displayed in the body of the document (so the \ae is right, just not in the citation). I attempted wrapping the command in {..}:

author = {... Hornb{\ae}k, Kasper},

but this gave me the same error. If I remove \ae from the citation, though, I don't get the ligature inserted for me.

How can I use an explicit ligature in a bibliographic reference?

  • 2
    Hornb{\ae}k will work Jul 10, 2013 at 13:16
  • 2
    @StevenB.Segletes's suggestion should work, but if it doesn't (as you said), try Hornb\ae k instead -- \aek is certainly not a (standard) macro. Jul 10, 2013 at 13:38
  • 3
    The reason why {\ae} gave you the same error is that you residual files left over from the failed compile. Delete the .aux and .bbl file and then recompile. cc: @SeanAllred Jul 10, 2013 at 13:40
  • 1
    @StevenB.Segletes :( and I didn't clean the build files while making the MWE, either... removing residuals and re-building with {\ae} worked. Thanks.
    – simont
    Jul 10, 2013 at 13:44
  • 3
    Note that Danish æ is a character on its own, rather than a ligature.
    – egreg
    Jul 10, 2013 at 13:47


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