Is there any guidance on how to properly cite when using the alphabetic style from BiBLaTeX? I am looking for some specifications on how to use the alphabetic style for citing properly. I know that there are different solutions and that this is highly related to personal preference or specific requirements. But maybe there is some common way to do it. Consider the following three examples:


  
  [...] was already shown in 1998 by Johnson et al. [JHS98] to demonstrate the specific deployment.
  [...] was already shown in 1998 by Johnson et al. to demonstrate the specific deployment [JHS98].
  [...] was already shown in 1998 by [JHS98] to demonstrate the specific deployment.
  


Which one would you consider the most standard or most used way?
Numbers 1. and 2. sound perfectly fine to me and are a matter of your personal style. 3. sounds a little unpolished to me and an editor or copy editor might smooth it to one of 1. or 2.