I. Sakho. (2011). Energy Resonances for $^1P^o,$ $^1D^e,$ $^1F^o,$ $^1G^e,$ and $^1H^o$ Autoionizing States of the Helium Isoelectronic Series Below the $n=2-4$ Hydrogenic Thresholds. Journal of Atomic and Molecular Sciences. 2 (1). 20-42. doi:10.4208/jams.062910.072810a