How to avoid using "I" in a research paper in case of referring to my previous work? As I know, using "I" and "we" should be avoided in research paper writing.

But in one of my paper, I am the only one author.

And in the introduction I wrote something like AA et al. proved that ..., BB et al. found that ..., CC et al. stated that .... 

Then the problem is that I want to refer to one of my previous research that I had conducted with Mr.CC. I and Mr.CC are the only two authors in those researches.

In this case, which one should I write?
(1) I and CC confirmed that ....
(2) My name and CC confirmed that ....
(3) The author and CC confirmed that ....
(4) Our group confirmed that ....

For me, I think the (2) sounds awkward. (4) may not be able to use because I am not in his group in "CC et al. stated that ....". But I am not sure whether the (1) and (3) are suitable.
Thank you very much in advanced.

For more information : I did not involve in "CC et al. stated that ....". This is the result of his team. But I involve in "I and CC confirmed that ...." which is the work that only I and CC did it. So CC will be referred two times in this paper.
There are two options I know of (I've seen both). 

One is to ignore that the person you are referring to is one of the authors, and write exactly the same way as if they were a third party. I guess this makes some sort of sense if there is no direct link between the two sets of work.

The other option is to use 'the first author' (or 'the second author', as applicable).