Zhi-Wen Wang, Yuan-Yuan Qi & Lei Sha. (2020). Fine Structures of $1s^2np$ and $1s^2nd$ States for $Zn^{27+}$ Ion.
            <i>Journal of Atomic and Molecular Sciences</i>. <i>3</i> (1).
            59-63.
         doi:10.4208/jams.032211.041611a