MMA2009 P.Code=SergN ===============------------------------------ First Name =Natalija Last Name =Sergejeva Title = Institution =Daugavpils University Street Address =Parades 1 City =Daugavpils State =Latvia Zip Code =LV5400 Telephone =+37128342971 FAX = E-mail =natalijasergejeva@inbox.lv URL = Title of talk and AMS Subject Classification=