This means you have to run LaTeX a number of times. The approach of putting only relevant text in curly brackets is the most feasible if using a template under the control of a publisher, such as for journal submissions.
This concerns words such as editors, and, or in as well as a proper typographic layout. Despite its name, the plain style does a pretty good job look at the output of this tutorial to see what I mean. Each pass will perform a particular task until it has managed to resolve all the citation references.
The second command is the one that actually specifies the. As you can guess, all you have to do is follow its instructions, and run LaTeX for the third time, and the document will be output as expected, without further problems. However, it is fairly straight-forward.
Karam and Drake, John W. Modifications of three standard styles plain, abbrv and alpha are provided with urlbst. Using curly braces around single letters is also to be avoided if possible, as it may mess up the kerning, especially with biblatex,  so the first step should generally be to enclose single words in braces.
For example, Google Scholar offers the option to return properly formatted output, which can also be turned on in the settings page.
To process your document from within vim, you must explicitly name the file without the file extension for bibtex to work, as is shown below: :! Medium Manner or way a work was communicated or distributed.