Andrea Sella (27 August 2008). "Raschig's Rings". Chemistry World. 5 (9): 83.
doi.org
Schultes, M. (January 2003). "Raschig Super-Ring: A New Fourth Generation Packing Offers New Advantages". Chemical Engineering Research and Design. 81 (1, International Conference on Distillation and Absorption): 48–57. doi:10.1205/026387603321158186.