@article{IM2_2021_85_4_a3,
     author = {M. E. Kazarian and S. K. Lando and S. M. Natanzon},
     title = {On framed simple purely real {Hurwitz} numbers},
     journal = {Izvestiya. Mathematics },
     pages = {681--704},
     publisher = {mathdoc},
     volume = {85},
     number = {4},
     year = {2021},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2021_85_4_a3/}
}