I just found this little jewel at the always interesting blog Pileta de Prehistoria:
Ofelia Barroso del Río y Federico del Río Berguño. Arte Rupestre. La Prehistoria Ilustrada del Oriente de Asturias (Rock Art. The Illustrated Prehistory of the Asturian East). Direct download here (PDF 3.24 MB).
A graphic and text review of the Paleolithic art, (32-11 thousand years ago) of this distinct district of the Franco-Cantabrian region that looks quite nice. Text in Spanish but many many images that are surely the main attraction of this e-book.