Cremaschi, Mauro, and Alan Busacca. 1994. “Deep Soils on Stable or Slowly Aggrading Surfaces: Time Versus Climate As Soil-Forming Factors. The Ferretto-Type Paleosol, a Case Study: The Crocetta Profile (Gazzola, Piacenza, Northern Italy)”. Geografia Fisica E Dinamica Quaternaria 17 (1): 19-28. https://www.gfdq.glaciologia.it/index.php/GFDQ/article/view/677.