1. Ragulskis K., Ragulskis L., Kibirkštis E., Augutis S. V., Vainilavičius D., Miliūnas V., Pauliukaitis D. Measurement of vibrations of rotating elements in a folding machine. Journal of Measurements in Engineering, Vol. 3, Issue 1, 2015, p. 9-16.
2. Kibirkštis E., Augutis S. V., Vainilavičius D., Miliūnas V., Pauliukaitis D., Ragulskis L. Effect of dynamic regime of rollers of pocket folding machine to quality of printing products. Journal of Vibroengineering, Vol. 17, Issue 6, 2015, p. 2869-2881.
3. PeiponenK. E., Myllyla R., Priezzhev A. V. Optical Measurement Techniques – Innovations for Industry and the Life Sciences. Springer, 2009, p. 155.
4. Jayakumar T., Thavasimuthu M. Practical Non-Destructive Testing. Woodhead, Cambridge, 2002, p. 184.
5. Rastogi P. K. Optical Measurement Techniques and Applications. Artech House Incorporated, 1997, p. 433.