1. EU countries legislation restriction. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex:32004L0042.
2. Technical Overview of Volatile Organic Compounds, EPA, 2017. https://www.epa.gov/indoor-air-quality-iaq/technical-overview-volatile-organic-compounds.
3. Volatile Organic Compounds (VOC) and Consumer Products Regulations. https://www.chemsafetypro.com/Topics/VOC/What_Are_Volatile_Organic_Compounds_(VOC)_and_Overview_of_Global_VOC_Regulations.html.
4. R. Oppl, T. Neuhaus, Emission specifications in Europe and the US – Limit values (TVOC, LCI, CREL, ...) in critical discussion, Indoor Air, Paper ID: 953 (2008), 17–22 August 2008, Copenhagen, Denmark.
5. China's restrictions on any volatile organic compounds. http://www.mee.gov.cn/.