Getting secondary citations right

Question

I have some questions regarding secondary citations (in an computer-science research paper that should be published in a journal). I know that they should be avoided when possible, but it is not always that easy. More specifically, my situation is this:

Article A says:

The average value of ... in ... is ... [B]. [C]’s study says that in ... the value is ...

This statement is exactly what i need for my paper. If I read [B] and [C], I see that [A] cited them correctly and if I would have found these two other articles myself, I would have written the same.

Now how to cite this in a correct way?

1. [B] and [C] say (cited in [A]) ...

   and do a “bad” secondary quote;

2. [B] and [C] say ...

   and neglect the investigation done by [A] and peform citation plagiarism;

3. [A] says ...

   and neglect that the data was the achievement of [B] and [C].

4. [A] says based on the findings of [B] and [C] ...

   and do a secondary quote again.

Answer 1

If you write about something originally stated in B and C, you should always read B and C to make sure that's actually what they said (which you say you've done) and cite them. (This rules out Option 3.)

Whether or not to cite A depends on how you use A.

• You are using intellectual content from A (the interpretation/summary of B and C), so you should cite A also. (Another example of this is How to cite the original source of an algorithm and a secondary source that provides a clearer description of the algorithm?). Option 4 indicates clearly what content comes from A and what comes from B and C, so it's a good way to cite it.
• If you weren't using any intellectual content (interpretation, summarization, curation of references) from A, but just happened to come by B and C via A, you may not need to cite A (see e.g. Is there a problem with citing the original source instead of the source where the information was first found?). However, based on your description, you are using A's interpretation, so that rules out Option 2.

The links (1,2) you have given to support your assertion that secondary citations are "bad" are being misinterpreted. Both of those advise against the practice of only citing the secondary source and not also tracking down the original. The third link you brought up (3) says not to use A's statements about B and C without citing A (Option 2).