@article{IM2_1969_3_3_a3,
     author = {A. I. Loginov},
     title = {Commutative symmetric operator algebras in {a~Pontrjagin} space},
     journal = {Izvestiya. Mathematics},
     pages = {515--535},
     year = {1969},
     volume = {3},
     number = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1969_3_3_a3/}
}