There is a research Paper Y which presents some experimental result. The author has cited Paper X to justify and explain the reason of that result. I am writing a review paper and included the result of Paper Y.
Can I cite Paper X in the review paper to give the justification of the result by Paper Y as already done by the Paper Y itself? Or will it be somehow called mindless copying from Paper Y? And should I cite Paper Y also (along with X) while including the correlation between result (Y) and the reason (X) as the author of Y was the first to correlate the two?