Machado, G., M. Vavrdová, P. E. Fonseca, H. I. Chaminé, y F. T. Rocha. 2011. «Dating and Differentiation of Geological Units in Highly Deformed and Metamorphosed Rocks – Can Palynology Help? Examples from the Ossa-Morena Zone (W Portugal)». Trabajos De Geología 30 (30). https://reunido.uniovi.es/index.php/TDG/article/view/154.