Good style for frequent references to some paper I have an document extending paper [A &amp; B, 2000]

On my work, I make many references to [A &amp; B, 2000], some times several times on the same paragraphs as there is some need to compare both approaches. 

How do I make reference to [A &amp; B, 2000] without being redundant?

Example:

 Our work compares with [A &amp; B, 2000] on the following:
  - The approach presented in [A &amp; B, 2000] makes (x) assumption on (...)
  - The (something) differ from those of [A &amp; B, 2000] on (...)
  - Performance of X was not reported by [A &amp; B, 2000]


(there is quite more content in between the references on the actual document, but still look overwhelming)
Check your target journal's style guide or advice to authors, but my approach is to use the citation format the first time I mention it and then just mention the authors by name or pronoun when I refer to them later. E.g:


  Our work compares with [A &amp; B, 2000] on the following:
    - The approach presented by A &amp; B makes (x) assumption on (...)
    - The (something) differ from those of A &amp; B on (...)
    - Performance of X was not reported by A &amp; B


Even that can get redundant. You might say say:


  Throughout the following section, we compare our work to [A &amp; B, 2000]. In their work, they make assumptions about (X) ... Additionally, (Y) differs between A &amp; B's method and our because ... They also do not present performance of (Z) in their work. 


It depends a bit on your own style, but my approach is always a bit more conversational.