.
.
Quantum Systems at The Brink. Existence and Decay Rates of Bound States at Thresholds; Atoms. arXiv:1908.05016. 2019 :14.
. Quantum Systems at The Brink. Existence and Decay Rates of Bound States at Thresholds; Helium. arXiv:1908.04883. 2019 :25.
.