1. Natural gas odorization;Tenkrat,2010
2. Sulfur-free odorization with gasodor S-free—a review of the accompanying research and development activities;Graf;Energy Fuels,2007
3. E. Isbilen KK, M. Yasar, U. Doldur, US patent, 2016, (US20160215226 A1).
4. U. Mueller JNs, US patent, 2008, (US20080256847 A1).
5. G. Mansfeld UR, F. Henke, H. Kaesler, US patent, 2006, (US7108803 B1).