How do I reference papers correctly in my masters thesis? [duplicate]

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• Getting secondary citations right 1 answer

I have searched but not have found a similar question, although I am sure a duplicate exists.

I am currently in the process of writing my masters thesis. I am being very careful about my sources and organizing all my read papers using Mendeley.

Suppose I am reading Paper1 by Eddy, S. Paper one makes a statement such as:

Proteins, RNA and other features in genomes can usually be classified into families of related sequences and structures (Henikoff et al., 1997).

If I paraphrase this using my own words and use it in my paper which will use the statement in a different context, who do I give credit too?

Do I reference Henikoff again even though I have not read that paper? Or do I reference Eddy even though (and I assume) he is a secondary source on this.

On an unrelated note, I am having a very hard time writing the thesis. Any help would be appreciated.