A Differential Operator Technique for Restoring Degraded Signals and Images. - John S. Ostrem; David G. Falconer (IEEE Trans. Pattern Anal. Mach. Intell., 1981)

Automatic signature verification using a three-axis force-sensitive pen. - Hewitt D. Crane; John S. Ostrem (IEEE Trans. Syst. Man Cybern., 1983)