Multiplicity results for positive solutions to non-autonomous elliptic problems. Qiao, Ning; Wang, Zhi-Qiang — 1999 Electronic Journal of Differential Equations (EJDE) [electronic only]
On the Zagreb index of quasi-tree graphs. Qiao, Sheng Ning — 2010 Applied Mathematics E-Notes [electronic only]
The number of spanning trees and chains of graphs. Qiao, Sheng Ning; Chen, Bing — 2009 Applied Mathematics E-Notes [electronic only]