You would like to include the following sentence in your paper from research done by Atkinson and Shiffrin in 1968 and 1971:

"The three-system approach to memory states that for information to be remembered, it must travel through different memory storage systems or stages."

How would you appropriately cite this in-text?

A. (1968, 1971)
B. (Atkinson & Shiffrin)
C. Atkinson & Shiffrin, (1968, 1971)
D. (Atkinson S. Shiffrin 1048 1071)