1. Plastics Insight. Resin Prices. May 2020.
2. Various sources containing current prices in May 2020 (consider that prices are relatively low due to coronavirus slow down of economy).
3. Effects of reprocessing conditions on the properties of unfilled and talc-filled polypropylene
4. Metal Matrix Composite Syntactic Foams for Light-Weight Structural Materials. Reference Module in Materials Science and Materials Engineering;Orbulov,2021
5. Handbook of Material Weathering;Wypych,2018