OECD (2021), "90 Optical, photographic, cinematographic, precision, medical or surgical instruments etc.: Korea: Harmonised System 2012",
in
International Trade by Commodity Statistics Volume 2020 Issue 6: Austria, Korea, Slovenia, Spain, Turkey, OECD Total, EU28-Extra,
OECD Publishing, Paris,
https://doi.org/10.1787/892df2f5-en.