昆明冶金高等专科学校学报 ›› 2016, Vol. 32 ›› Issue (3): 59-62.DOI: 10. 3969/j. issn. 1009—0479.2016.03.012
牛华伟1,兰奇逊2
NIU Huawei1,LAN Qixun2
1. Department of Mathematics,Pingdingshan Institute of Education, Pingdingshan, Henan 467000,China ;
2. School of Mathematics and Physics,Henan University of Urban Construction, Pingdingshan, Henan 467036,China