Mathematical Notes
Mathematical Notes > 2002 > 71 > 1-2 > 154-165
Mathematical Notes > 2002 > 72 > 5-6 > 833-840
Mathematical Notes > 2003 > 74 > 1-2 > 157-176
Mathematical Notes > 2006 > 80 > 1-2 > 3-10
Mathematical Notes > 2013 > 94 > 5-6 > 703-714
Mathematical Notes > 2013 > 94 > 5-6 > 968-973
Mathematical Notes > 2014 > 96 > 3-4 > 379-390
Mathematical Notes > 2016 > 100 > 3-4 > 639-641