Barros, Omar Neto Fernandes, Luiza Saito, and Paulo Noffis. 2004. “Concept of Time: Relations Between Alteration Degrees and Chronosequence and the Geomorphological Surfaces”. Semina: Ciências Exatas E Tecnológicas 21 (4):67-76. https://doi.org/10.5433/1679-0375.2000v21n4p67.