Exner, Pavel, and Diana Barseghyan. “Spectral Analysis of Schrödinger Operators With Unusual Semiclassical Behavior”.
Acta Polytechnica
53, no. 3 (January 3, 2013). Accessed July 16, 2025.
https://ojst.is.cvut.cz/ojs/index.php/ap/article/view/1801
.