Implementation of quaternion mathematics for biometric security. - Fatma Khallaf; Walid El-Shafai; El-Sayed M. El-Rabaie; Mahmoud Nasr; Mohammed Essam; E. S. Shoukralla; Saied M. Abd El-atty; Fathi E. Abd El-Samie (Multim. Tools Appl., 2024)