A Method Based on the Continuous Spectrum Analysis for Fingerprint Image Ridge Distance Estimation. - Xiaosi Zhan; Zhaocai Sun; Yilong Yin; Yayun Chu (FSKD (2), 2005)

Fingerprint Ridge Distance Estimation: Algorithms and the Performance. - Xiaosi Zhan; Zhaocai Sun; Yilong Yin; Yayun Chu (ICB, 2006)