@article{ZNSL_1995_229_a2,
     author = {Kh. D. Ikramov and L. \'El'zner},
     title = {On normal matrices with normal principal submatrices},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {63--94},
     publisher = {mathdoc},
     volume = {229},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1995_229_a2/}
}