@article{RM_2022_77_2_a0,
     author = {D. E. Apushkinskaya and A. I. Nazarov},
     title = {The normal derivative lemma and surrounding issues},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {189--249},
     publisher = {mathdoc},
     volume = {77},
     number = {2},
     year = {2022},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_2022_77_2_a0/}
}