Use of QR codes in academic publications Modern academic publishing is based to a large extent on the use of the Internet, and many of us consult articles or even books mostly in PDF format rather than hard copy. URL links to both reference material, and data sets or complementary material the author makes available to the reader are becoming commonplace, and are easily accessed from within a document that is consulted in electronic form.

However, in some cases the document can only be accessed in paper, which makes following a URL awkward. Examples of this could be some editions of books available only in paper form, or CVs (as discussed in this question on SE: Is it advisable to have many hyperlinks in an academic CV?).

In similar circumstances, both the manufacturing industries and the marketing sector tend to use QR codes that are easily scannable from a mobile device, such as this one containing the URL of Academia on SE:



To date, I have personally never seen the use of QR codes in academia.

My question is therefore: what major factors make the use of this technology less likely to become commonplace in academic publishing - or more likely, as the case may be?

Edit: thanks to a comment below, my attention has been brought to some scientific books by Elsevier and O'Reilly that do contain QR-codes to enrich content with online material. In both cases, the field were Computer Science and Technology in Medicine.
I think this is a matter of convention and necessity.  As you already point out, most documents are online.  If something is online or in pdf form, having a QR code that is scanned with a phone is a waste of space, as the user can just click on the link instead.

In the case you are describing, I find it rare that any document would be only available in paper form, if it was made at any time since the invention of the QR codes existence (which it would need to be in order to have one).  

The question also seems to be a rare situation.  You are saying a new document is published, but it is only available in paper, but it contains other information that needs to be seen online.  It is hard to imagine a document which is in paper, that contains some valuable data that needs to be viewed on an electronic system, in which the time saved from scanning a QR code on a phone and dealing with a phone screen outweighs the use of a tiny url or permalink typed into a computer.