Ghosh, Pallab (8 October 2014). "Cave paintings change ideas about the origin of art". BBC News. BBC News. "The minimum age for (the outline of the hand) is 39,900 years old, which makes it the oldest hand stencil in the world," said Dr Aubert. "Next to it is, and this is one of the oldest figurative depictions in the world, if not the oldest one," he told BBC News. There are also paintings in the caves that are around 27,000 years old, which means that the inhabitants were painting for at least 13,000 years."
Pike, A. W. G.; Hoffmann, D. L.; García-Diaz, M.; Pettitt, P. B.; Alcolea, J.; De Balbín, R.; González-Sainz, C.; de las Heras, C.; Lasheras, J. A.; Montes, R.; Zilhão, J. (15 June 2012). "U-Series Dating of Paleolithic Art in 11 Caves in Spain". Science. 336 (6087): 1409–1413. Bibcode:2012Sci...336.1409P. doi:10.1126/science.1219957. PMID22700921. S2CID7807664. Abstract: "... minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol".
S. Arscott "On evaporation via an inclined rotating circular lift-off shadow or stencil mask" J. Vac. Sci. Technol. B 37, 011602 (2019). doi:10.1116/1.5057404.
D. Eschimese et al "Size and shape control of a variety of metallic nanostructures using tilted, rotating evaporation and lithographic lift-off techniques" Sci. Rep. B 9, 7682 (2019). doi:10.1038/s41598-019-44074-w.
Pike, A. W. G.; Hoffmann, D. L.; García-Diaz, M.; Pettitt, P. B.; Alcolea, J.; De Balbín, R.; González-Sainz, C.; de las Heras, C.; Lasheras, J. A.; Montes, R.; Zilhão, J. (15 June 2012). "U-Series Dating of Paleolithic Art in 11 Caves in Spain". Science. 336 (6087): 1409–1413. Bibcode:2012Sci...336.1409P. doi:10.1126/science.1219957. PMID22700921. S2CID7807664. Abstract: "... minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol".
Pike, A. W. G.; Hoffmann, D. L.; García-Diaz, M.; Pettitt, P. B.; Alcolea, J.; De Balbín, R.; González-Sainz, C.; de las Heras, C.; Lasheras, J. A.; Montes, R.; Zilhão, J. (15 June 2012). "U-Series Dating of Paleolithic Art in 11 Caves in Spain". Science. 336 (6087): 1409–1413. Bibcode:2012Sci...336.1409P. doi:10.1126/science.1219957. PMID22700921. S2CID7807664. Abstract: "... minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol".
Pike, A. W. G.; Hoffmann, D. L.; García-Diaz, M.; Pettitt, P. B.; Alcolea, J.; De Balbín, R.; González-Sainz, C.; de las Heras, C.; Lasheras, J. A.; Montes, R.; Zilhão, J. (15 June 2012). "U-Series Dating of Paleolithic Art in 11 Caves in Spain". Science. 336 (6087): 1409–1413. Bibcode:2012Sci...336.1409P. doi:10.1126/science.1219957. PMID22700921. S2CID7807664. Abstract: "... minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol".