Siberian Mathematical Journal
Siberian Mathematical Journal > 2009 > 50 > 3 > 533-540
Siberian Mathematical Journal > 2009 > 50 > 3 > 560-566
Siberian Mathematical Journal > 2009 > 50 > 3 > 533-540
Siberian Mathematical Journal > 2009 > 50 > 3 > 560-566