I am writing an R presentation in an .Rpres file. I published my presentation on Rpubs here: http://rpubs.com/cr517/presentationGurdon I have images stored in PDF files. I am trying to include them in my presentation, unsuccesfully. I am using this command to include the images:

the same as for .jpg. This command does not result in the display of the image. I have tried to follow these answers but could not make it work:
R markdown: can I insert a pdf to the r markdown file as an image?
Add pdf file in Rmarkdown file
If somebody could help me, that would be much appreciated. That would spare me the re-run of my code exporting images in .jpg format.
Thank you so much.