Since Valasek's discovery of the ferroelectric properties of Rochelle salt nearly 60 years ago, ferroelectricity has been regarded as one of the tradi- tional branches of dielectric physics. It has had important applications in lattice dynamics, quantum electronics, and nonlinear optics. The study of electron processes in ferroelectrics was begun with VUL's investigations of the ferroelectric properties of barium titanate [1.1]. In- trinsic and extrinsic optical absorption, band structure, conductivity and photoconductivity, carrier mobility. and transport mechanisms were examined in this...