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@article{MV_1975_27_1_a2, author = {Gh. Constantin}, title = {On operators with the same spectrum}, journal = {Matemati\v{c}ki vesnik}, pages = {25 }, publisher = {mathdoc}, volume = {27}, number = {1}, year = {1975}, url = {http://geodesic.mathdoc.fr/item/MV_1975_27_1_a2/} }
Gh. Constantin. On operators with the same spectrum. Matematički vesnik, Tome 27 (1975) no. 1, p. 25 . http://geodesic.mathdoc.fr/item/MV_1975_27_1_a2/