Here is an citation from a scientific article:

> 
> In **a** well known article, Einstein, Rosen, and Podolsky have given an example of a hypothetical experiment capable of testing [...].
> 
> 
> 

Which article should be used before *well-known*: **a** or **the**?

The article that the authors are refering to is well known to everyone familiar with the subject, it's fair to say that to every reader of the paper. The article is referenced to, if that matters.

As far as I know, we use the definite article to [refer to people or objects that are unique.](http://www.edufind.com/english-grammar/definite-article/) This paper is as unique as it can be. Is it correct to use the indefinite article in this case? 

Doesn't the cited sentence mean that there are many well-known papers on the subject and the authors refer to just one of them?