Third-order geomorphometric variables (derivatives): definition, computation and utilization of changes of curvatures. - Jozef Minár; Marián Jenco; Ian S. Evans; Jozef Minár Jr.; Martin Kadlec; Jozef Krcho; Jan Pacina; Libor Burian; Alexandra Benová (Int. J. Geogr. Inf. Sci., 2013)