When making an academic presentation it is often valuable to quote the literature. Quote means to speak. Don’t write it down, it is not valuable.
There is an increasing tendency to show references in a slide or series of slides. The value of this appears to be in adding some strength to an argument that “Fisher et al in their seminal paper said x”. The reality is that if the reference is, as you suggest, seminal, then the audience will know the paper of which you speak. If it is not then their ability to write down accurately the reference you have shown on the screen will be virtually zero by the time you have moved on to your next point. Or they will be distracted from your next point as they do write down the reference, usually as it is in tiny print. A list of references at the end of your presentation simply shows you have forgotten the difference between a presentation and a document.
If you feel the audience will need or want to take the exact reference away from the meeting, then make it available in an easy manner, along with other information, perhaps even a full copy of the paper. A short url (from Google) goo.gl/mZkZRM is a quick way that many will understand or even a QR code. Such codes challenge many audiences as it often requires specific software that may not be readily available to all.
If a reference is of value, simply quote it. You wouldn’t read out the exact volume and page, so don’t write it either.