1. Łukomski A., The frames of machines and equipment, Part 1. Des. Eng. Cons. 93, (2015)
2. Baumeister E., Hohlkugelkomposit - Characterization of thermal and mechanical properties of a new lightweight construction material. (Doctoral dissertation. Magdeburg 2004)
3. Łukomski A., The frames of machines and equipment, Part 2. Design. Eng. Constr. 94/95, (2015)
4. http://www.promus.pl/index.html