Limit the number of items

This is not currently possible, partially also because "last" is not well-defined -- bibbase does not know whether you add new entries in the front or the back (or the middle) of your bibtex file. What you can do, however, is to use a filter, e.g., if you add "&filter=year:2016" to your URL it should only list papers from 2016. This works on any field, so if you really wanted to, you could go in and edit your bibtex file to mark the ones you want to list with a special field (e.g., show={1}), and then filter on that.